fix dates

* 重要改动：提供了一个定义定理类环境的命令 \elegantnewtheorem；
* 重要改动：为所有内置定理类环境提供了带星号的版本，带星号的定理类环境不会编号；fix #167
* 将 TeX Gyre Termes 改为 TeX Gyre TermesX，使英文部分字形与 newtx
  系列宏包更相近；
* 重写了内置定理类环境的实现方法。

.gitignore

@@ -0,0 +1,247 @@
+## Core latex/pdflatex auxiliary files:
+*.aux
+*.lof
+*.log
+*.lot
+*.fls
+*.out
+*.toc
+*.fmt
+*.fot
+*.cb
+*.cb2
+.*.lb
+.DS_Store
+clean.bat
+elegant*-cn.pdf
+elegant*-en.pdf
+*.dates
+
+## Intermediate documents:
+*.dvi
+*.xdv
+*-converted-to.*
+# these rules might exclude image files for figures etc.
+# *.ps
+# *.eps
+# *.pdf
+
+## Generated if empty string is given at "Please type another file name for output:"
+.pdf
+
+## Bibliography auxiliary files (bibtex/biblatex/biber):
+*.bbl
+*.bcf
+*.blg
+*-blx.aux
+*-blx.bib
+*.run.xml
+
+## Build tool auxiliary files:
+*.fdb_latexmk
+*.synctex
+*.synctex(busy)
+*.synctex.gz
+*.synctex.gz(busy)
+*.pdfsync
+
+## Auxiliary and intermediate files from other packages:
+# algorithms
+*.alg
+*.loa
+
+# achemso
+acs-*.bib
+
+# amsthm
+*.thm
+
+# beamer
+*.nav
+*.pre
+*.snm
+*.vrb
+
+# changes
+*.soc
+
+# cprotect
+*.cpt
+
+# elsarticle (documentclass of Elsevier journals)
+*.spl
+
+# endnotes
+*.ent
+
+# fixme
+*.lox
+
+# feynmf/feynmp
+*.mf
+*.mp
+*.t[1-9]
+*.t[1-9][0-9]
+*.tfm
+
+#(r)(e)ledmac/(r)(e)ledpar
+*.end
+*.?end
+*.[1-9]
+*.[1-9][0-9]
+*.[1-9][0-9][0-9]
+*.[1-9]R
+*.[1-9][0-9]R
+*.[1-9][0-9][0-9]R
+*.eledsec[1-9]
+*.eledsec[1-9]R
+*.eledsec[1-9][0-9]
+*.eledsec[1-9][0-9]R
+*.eledsec[1-9][0-9][0-9]
+*.eledsec[1-9][0-9][0-9]R
+
+# glossaries
+*.acn
+*.acr
+*.glg
+*.glo
+*.gls
+*.glsdefs
+
+# gnuplottex
+*-gnuplottex-*
+
+# gregoriotex
+*.gaux
+*.gtex
+
+# htlatex
+*.4ct
+*.4tc
+*.idv
+*.lg
+*.trc
+*.xref
+
+# hyperref
+*.brf
+
+# knitr
+*-concordance.tex
+# TODO Comment the next line if you want to keep your tikz graphics files
+*.tikz
+*-tikzDictionary
+
+# listings
+*.lol
+
+# makeidx
+*.idx
+*.ilg
+*.ind
+*.ist
+
+# minitoc
+*.maf
+*.mlf
+*.mlt
+*.mtc[0-9]*
+*.slf[0-9]*
+*.slt[0-9]*
+*.stc[0-9]*
+
+# minted
+_minted*
+*.pyg
+
+# morewrites
+*.mw
+
+# nomencl
+*.nlg
+*.nlo
+*.nls
+
+# pax
+*.pax
+
+# pdfpcnotes
+*.pdfpc
+
+# sagetex
+*.sagetex.sage
+*.sagetex.py
+*.sagetex.scmd
+
+# scrwfile
+*.wrt
+
+# sympy
+*.sout
+*.sympy
+sympy-plots-for-*.tex/
+
+# pdfcomment
+*.upa
+*.upb
+
+# pythontex
+*.pytxcode
+pythontex-files-*/
+
+# thmtools
+*.loe
+
+# TikZ & PGF
+*.dpth
+*.md5
+*.auxlock
+
+# todonotes
+*.tdo
+
+# easy-todo
+*.lod
+
+# xmpincl
+*.xmpi
+
+# xindy
+*.xdy
+
+# xypic precompiled matrices
+*.xyc
+
+# endfloat
+*.ttt
+*.fff
+
+# Latexian
+TSWLatexianTemp*
+
+## Editors:
+# WinEdt
+*.bak
+*.sav
+
+# Texpad
+.texpadtmp
+
+# Kile
+*.backup
+
+# KBibTeX
+*~[0-9]*
+
+# auto folder when using emacs and auctex
+./auto/*
+*.el
+
+# expex forward references with \gathertags
+*-tags.tex
+
+# standalone packages
+*.sta
+
+# generated if using elsarticle.cls
+*.spl

License

@@ -0,0 +1,416 @@
+The LaTeX Project Public License
+=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
+
+LPPL Version 1.3c  2008-05-04
+
+Copyright 1999 2002-2008 LaTeX3 Project
+    Everyone is allowed to distribute verbatim copies of this
+    license document, but modification of it is not allowed.
+
+
+PREAMBLE
+========
+
+The LaTeX Project Public License (LPPL) is the primary license under
+which the LaTeX kernel and the base LaTeX packages are distributed.
+
+You may use this license for any work of which you hold the copyright
+and which you wish to distribute.  This license may be particularly
+suitable if your work is TeX-related (such as a LaTeX package), but 
+it is written in such a way that you can use it even if your work is 
+unrelated to TeX.
+
+The section `WHETHER AND HOW TO DISTRIBUTE WORKS UNDER THIS LICENSE',
+below, gives instructions, examples, and recommendations for authors
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+WHETHER AND HOW TO DISTRIBUTE WORKS UNDER THIS LICENSE
+======================================================
+
+This section contains important instructions, examples, and
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+
+Choosing This License or Another License
+----------------------------------------
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+Here is an example of such a notice and statement:
+
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+Given such a notice and statement in a file, the conditions
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+Derived Works That Are Not Replacements
+---------------------------------------
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+
+Important Recommendations
+-------------------------
+
+ Defining What Constitutes the Work
+
+   The LPPL requires that distributions of the Work contain all the
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+   This could, for example, be achieved by explicitly listing all the
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+   in that place.  In the absence of an unequivocal list it might be
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+   entitled to make reasonable conjectures as to which files comprise
+   the Work.
+

README.md

@@ -0,0 +1,37 @@
+<!-- Author : Dongsheng Deng & Liam Huang-->
+<!-- Program Email: elegantlatex2e@gmail.com -->
+
+[Homepage](https://elegantlatex.org/) | [Github](https://github.com/ElegantLaTeX/ElegantBook) | [CTAN](https://ctan.org/pkg/elegantbook) | [Download](https://github.com/ElegantLaTeX/ElegantBook/releases) | 
+
+![License](https://img.shields.io/ctan/l/elegantbook.svg) ![CTAN Version](https://img.shields.io/ctan/v/elegantbook.svg) ![Github Version](https://img.shields.io/github/release/ElegantLaTeX/ElegantBook.svg) ![Repo Size](https://img.shields.io/github/repo-size/ElegantLaTeX/ElegantBook.svg)
+
+-------
+
+# ElegantBook: 优美的 LaTeX 书籍模板 An Elegant LaTeX Template for Books 
+
+ElegantBook 是为 LaTeX 书籍写作而设计的模板，由 [Ethan Deng](https://github.com/EthanDeng) 和 [Liam Huang](https://github.com/Liam0205) 创立，现在主要由 [Ethan Deng](https://github.com/EthanDeng)、[乙醇](https://github.com/syvshc)和[死抠](https://github.com/sikouhjw)维护。如果你有其他问题、建议或者报告 bug，可以提交 issues 或者加入我们的 QQ 用户交流群：692108391。
+
+ElegantBook is designed for writing books, created by [Ethan Deng](https://github.com/EthanDeng) and [Liam Huang](https://github.com/Liam0205), and maintained by [Ethan Deng](https://github.com/EthanDeng), [syvshc](https://github.com/syvshc) and [sikouhjw](https://github.com/sikouhjw). Just enjoy it! If you have any questions, suggestions or bug reports, you can create issues or contact us at elegantlatex2e@gmail.com.
+
+
+## 致谢 Acknowledgement
+
+
+特别感谢 [sikouhjw](https://github.com/sikouhjw) 和 [syvshc](https://github.com/syvshc) 长期以来对于 Github 上 issue 的快速回应，以及各个社区论坛对于 ElegantLaTeX 相关问题的回复。特别感谢 ChinaTeX 以及 [LaTeX 工作室](http://www.latexstudio.net/)对于本系列模板的大力宣传与推广。
+
+Thank [sikouhjw](https://github.com/sikouhjw) and [syvshc](https://github.com/syvshc) for their quick response to Github issues and continuously support work for ElegantLaTeX community. Thank ChinaTeX and [LaTeX Studio](http://www.latexstudio.net/) for their promotion. 
+
+
+## 协议 License
+
+本模板发布遵循 LaTeX 项目公共许可证 1.3 c 或更高版本。
+如果是衍生作品，请务必加入协议声明和模板信息（github、CTAN 地址）。
+
+This work is released under the LaTeX Project Public License, v1.3c or later.
+
+
+## 衍生品 Derivative Works
+
++ [ElegantBookdown](https://github.com/XiangyunHuang/ElegantBookdown)：[XiangyunHuang](https://github.com/XiangyunHuang) 开发并维护的基于 ElegantBook 的 Bookdown 模板。
++ [bookdownplus](https://github.com/pzhaonet/bookdownplus)：应网友要求，[pzhaonet](https://github.com/pzhaonet) 在 bookdownplus 收录了 ElegantPaper 模板，并为 Mac 做了字体适配。
++ [PanBook](https://github.com/annProg/PanBook)：[annProg](https://github.com/annProg) 开发并维护的基于 Markdown 写作的工作流，收录了 ElegantBook 和 ElegantPaper 模板。

base.tex

@@ -1,34 +0,0 @@
-
-%% tikz setting
-\tikzset{x=1pt,y=1pt}
-\tikzset{elegant/.style={fill=main,draw=main},
-             null/.style={fill=white,draw=none}}
-             
-%% the triangle shape
-\newcommand{\triz}[2]{
-\begin{scope}[xshift=#1,rotate=#2]
-  \draw[elegant] (0,0) -- (105,6) .. controls (119,21) and (132,13) .. (135,12) .. controls (124,15) and (110,8) .. (107,-12) -- cycle;
-  \draw[null] (40,-0.5) -- (101,-4) -- (103,1)--cycle;
-\end{scope}
-}
-
-%% the ellipse shape +127
-\newcommand{\ellz}[1]{
-\begin{scope}[xshift=#1,yshift=3]
-\draw[elegant,rotate around={60:(0,-3)}](0,-3) ellipse (10.5 and 8.5);
-\draw[null](-3,-10) .. controls (-10,-6)  and (-2,6) .. (4.5,4) .. controls (0,3) and  (-4,-6) .. (-3,-10)--cycle;
-\end{scope}
-}
-
-%% the integration shape+147
-\newcommand{\intz}[1]{
-\begin{scope}[xshift=#1,yshift=2]
-\draw[elegant,draw=none,very thin] (-31,-14.5) .. controls (-17,-21)  and (-9,-8) .. (-3,0) .. controls (10,19) and (22,17) .. (29,9) .. controls (21,13) and (13,13) .. (3,-1) .. controls (-4,-11) and (-18,-27) .. (-31,-14.5) -- cycle ;
-\end{scope}
-}
-
-
-
-
-
-

elegantbook-en.tex

@@ -0,0 +1,797 @@
+\documentclass[11pt]{elegantbook}
+
+\title{An Elegant \LaTeX{} Template for Books}
+\subtitle{Classic Elegant\LaTeX{} Template}
+
+\author{Ethan Deng \& Liam Huang}
+\institute{Elegant\LaTeX{} Program}
+\date{Aug 15, 2022}
+\version{4.4}
+\bioinfo{Bio}{Information}
+
+\extrainfo{Victory won\rq t come to us unless we go to it. }
+
+\logo{logo-blue.png}
+\cover{cover.jpg}
+
+% modify the color in the middle of titlepage
+\definecolor{customcolor}{RGB}{32,178,170}
+\colorlet{coverlinecolor}{customcolor}
+\usepackage{cprotect}
+
+\addbibresource[location=local]{reference.bib} % bib
+
+\begin{document}
+
+\maketitle
+
+\frontmatter
+\tableofcontents
+
+\mainmatter
+
+\chapter{Elegant\LaTeX{} Templates}
+Elegant\LaTeX{} Program developers are intended to provide you beautiful, elegant, user-friendly templates. Currently, the Elegant\LaTeX{} is composed of \href{https://github.com/ElegantLaTeX/ElegantNote}{ElegantNote}, \href{https://github.com/ElegantLaTeX/ElegantBook}{ElegantBook}, \href{https://github.com/ElegantLaTeX/ElegantPaper}{ElegantPaper}, designed for typesetting notes, books, and working papers respectively. Latest releases are strongly recommended! This guide is aimed at briefly introducing the 101 of this template. For any other question, suggestion or comment, feel free to contact us on GitHub \href{https://github.com/ElegantLaTeX/ElegantBook/issues}{issues} or email us at \email{elegantlatex2e@gmail.com}.
+
+Contact Infos:
+\begin{itemize}
+  \item GitHub: \href{https://github.com/ElegantLaTeX/}{https://github.com/ElegantLaTeX/}
+  \item CTAN: \href{https://ctan.org/pkg/elegantbook}{https://ctan.org/pkg/elegantbook}
+  \item Download: \href{https://github.com/ElegantLaTeX/ElegantBook/releases}{release}, \href{https://github.com/ElegantLaTeX/ElegantBook/archive/master.zip}{latest version}
+\end{itemize}
+
+
+\section{Online Usage}
+You can visit \href{https://www.overleaf.com/}{Overleaf} to use our template online anywhere and anytime without local installation. To find our template, search \lstinline{elegantlatex} in the \lstinline{templates} or simply visit \href{https://www.overleaf.com/latex/templates?addsearch=elegantlatex}{search result}, choose the template you prefer and \lstinline{Open as Template} to own a copy yourself to edit freely. To learn more about Overleaf, please refer to \href{https://www.overleaf.com/learn}{Documentation}.
+
+
+\section{Portable Version}
+For portable version, simply download lastest ElegantBook-master from GitHub or CTAN (to be more accurate, download \lstinline{elegantbook.cls}) and save the file(s) under your working directory. This way of installation is simple and convenient, but you have to manually update \lstinline{cls} now and then.
+
+
+\section{Update Templates}
+You can use cmd/terminal to update the tlmgr itself and all the packages, the commands are:
+\begin{lstlisting}
+tlmgr update --self
+tlmgr update --all
+\end{lstlisting}
+
+To learn more, please refer to \href{https://tex.stackexchange.com/questions/55437/how-do-i-update-my-tex-distribution}{How do I update my \TeX{} distribution?}
+
+\section{Other Release Versions}
+If you are a \TeX{} Live 2018/2019/2020/2021 user and would like to update, the official solution is to uninstall the previous version. If you want to save the bother of uninstallation and re-installation, please copy \lstinline{elegantbook.cls} to the installation directory of \TeX{} Live 2022 (default: \lstinline|C:\texlive\2022\texmf-dist\tex\latex\elegantbook| ), run \lstinline{texhash} in cmd.
+
+\chapter{ElegantBook Settings}
+This template is based on the Standard \LaTeX{} book class, so the options of book class work as well (Note that the option of papersize has no effect due to \lstinline{device} option). The default encoding is UTF-8 while \TeX{} Live is recommended. The test environments are Win10/Ubuntu 20.04/macOS + \TeX{} Live 2022/ Mac\TeX{} 2022, either \hologo{pdfLaTeX} or \hologo{XeLaTeX} works fine for \lstinline{lang=en}.
+
+\section{Languages}
+We defined one option named \lstinline{lang} which has two basic values, \lstinline{lang=en} (default) , \lstinline{lang=cn}. Different values will alter the captions of figure/table, abstract name, refname, etc. You can use this option as
+
+\begin{lstlisting}
+\documentclass[en]{elegantbook} 
+\documentclass[lang=en]{elegantbook}
+\end{lstlisting}
+
+Besides the two basic language translation, our user provide more options, here is a short brief introduction to these translation. Since I am not familiar with these languages, I can't guarantee that the translations are correct, please comment on GitHub if you have some questions.
+
+\begin{itemize}
+  \item Italian translation \lstinline{lang=it}, provided by \href{https://github.com/VincentMVV}{VincentMVV} , please refer to \href{https://github.com/ElegantLaTeX/ElegantBook/issues/85}{Italian translation};
+  \item French translation \lstinline{lang=fr}, provided by \href{https://github.com/abfek66}{abfek66} , please refer to \href{https://github.com/ElegantLaTeX/ElegantBook/issues/85}{Italian translation};
+  \item Dutch Translation \lstinline{lang=nl}, provided by \href{https://github.com/inktvis75}{inktvis75} , please refer to \href{https://github.com/ElegantLaTeX/ElegantBook/issues/108}{Dutch Translation};
+  \item Hungarian translation \lstinline{lang=hu}, provided by \href{https://github.com/palkotamas}{palkotamas}, please refer to \href{https://github.com/ElegantLaTeX/ElegantBook/issues/111}{Hungarian translation};
+  \item Deutsch translation \lstinline{lang=de}, provided by Lisa, please refer to \href{https://github.com/ElegantLaTeX/ElegantBook/issues/113}{Deutsch translation};
+  \item Spanish translation \lstinline{lang=es}, provided by Gustavo A. Corradi, please refer to \href{https://github.com/ElegantLaTeX/ElegantBook/issues/133}{Spanish translation};
+  \item Mongolian translation \lstinline{lang=mn}, provided by \href{https://github.com/Altantsooj}{Altantsooj}, please refer to \href{https://github.com/ElegantLaTeX/ElegantBook/issues/137}{Mongolian translation};
+  \item Japanese translation \lstinline{lang=jp}, provided by \href{https://github.com/inusturbo}{inusturbo}, please refer to \href{https://github.com/ElegantLaTeX/ElegantBook/issues/172}{Japanese translation}.
+\end{itemize}
+
+\begin{remark}
+Chinese Characters  are acceptable \textbf{ONLY} in \lstinline{lang=cn}.
+\end{remark}
+
+\section{Device Mode Option}
+The option for device (\lstinline{device}) was originally used in ElegantNote, now we include this option in ElegantBook\footnote{Pictures have to be modified accordingly.} as well. Activate iPad mode in the following way\footnote{Default size: normal, A4 paper.}:
+\begin{lstlisting}
+\documentclass[pad]{elegantbook} %or
+\documentclass[device=pad]{elegantbook}
+\end{lstlisting}
+
+\section{Color Themes}
+This template contains 5 color themes, i.e., \textcolor{structure1}{\lstinline{green}}\footnote{Original default theme.}, \textcolor{structure2}{\lstinline{cyan}}, \textcolor{structure3}{\lstinline{blue}}(default), \textcolor{structure4}{\lstinline{gray}}, \textcolor{structure5}{\lstinline{black}}. You can choose \lstinline{green} with
+\begin{lstlisting}
+\documentclass[green]{elegantbook} %or
+\documentclass[color=green]{elegantbook}
+\end{lstlisting}
+
+
+\begin{table}[htbp]
+\caption{ElegantBook Themes\label{tab:color thm}}
+\centering
+\begin{tabular}{ccccccc}
+\toprule
+          & \textcolor{structure1}{green} 
+          & \textcolor{structure2}{cyan} 
+          & \textcolor{structure3}{blue}
+          & \textcolor{structure4}{gray} 
+          & \textcolor{structure5}{black} 
+          & Main Environments\\
+\midrule
+structure & \makecell{{\color{structure1}\rule{1cm}{1cm}}}
+        & \makecell{{\color{structure2}\rule{1cm}{1cm}}}
+        & \makecell{{\color{structure3}\rule{1cm}{1cm}}} 
+        & \makecell{{\color{structure4}\rule{1cm}{1cm}}} 
+        & \makecell{{\color{structure5}\rule{1cm}{1cm}}} 
+        & chapter  section  subsection \\
+main      & \makecell{{\color{main1}\rule{1cm}{1cm}}}
+        & \makecell{{\color{main2}\rule{1cm}{1cm}}}
+        & \makecell{{\color{main3}\rule{1cm}{1cm}}}
+        & \makecell{{\color{main4}\rule{1cm}{1cm}}}
+        & \makecell{{\color{main5}\rule{1cm}{1cm}}}
+        & definition  exercise  problem  \\
+second    & \makecell{{\color{second1}\rule{1cm}{1cm}}}
+        & \makecell{{\color{second2}\rule{1cm}{1cm}}}
+        & \makecell{{\color{second3}\rule{1cm}{1cm}}}
+        & \makecell{{\color{second4}\rule{1cm}{1cm}}}
+        & \makecell{{\color{second5}\rule{1cm}{1cm}}}
+        & theorem  lemma  corollary\\
+third     & \makecell{{\color{third1}\rule{1cm}{1cm}}}
+        & \makecell{{\color{third2}\rule{1cm}{1cm}}}
+        & \makecell{{\color{third3}\rule{1cm}{1cm}}}
+        & \makecell{{\color{third4}\rule{1cm}{1cm}}}
+        & \makecell{{\color{third5}\rule{1cm}{1cm}}}
+        & proposition\\
+\bottomrule
+\end{tabular}
+\end{table}
+
+If you want to customize the colors, please select \lstinline{nocolor} or use \lstinline{color=none} and declare the main, second, and third colors in the preamble section as follows:
+\begin{lstlisting}[frame=single]
+\definecolor{structurecolor}{RGB}{60,113,183}
+\definecolor{main}{RGB}{0,166,82}%
+\definecolor{second}{RGB}{255,134,24}%
+\definecolor{third}{RGB}{0,174,247}% 
+\end{lstlisting}
+
+\section{Cover}
+\subsection{Customized Cover}
+From v3.10, customized cover is allowed, you can choose or hide any element as you prefer. Current optional elements are:
+\begin{itemize}
+  \item title: \lstinline{\title}
+  \item subtitle: \lstinline{\subtitle}
+  \item author: \lstinline{\author}
+  \item institute: \lstinline{\institute}
+  \item date: \lstinline{\date}
+  \item version: \lstinline{\version}
+  \item extra information: \lstinline{\extrainfo}
+  \item cover image: \lstinline{\cover}
+  \item logo: \lstinline{\logo}
+\end{itemize}
+
+Besides, an extra command \lstinline{\bioinfo} is provided with two options--caption and content. For instance, if you want to display \lstinline{Username: 111520}, just type in
+
+\begin{lstlisting}
+\bioinfo{Username}{115520}
+\end{lstlisting}
+
+You can change the color of the horizontal bar of the cover by
+\begin{lstlisting}
+  \definecolor{customcolor}{RGB}{32,178,170}
+  \colorlet{coverlinecolor}{customcolor}
+\end{lstlisting}
+
+\subsection{Cover Image}
+The cover image used in this template is from \href{https://pixabay.com/en/tea-time-poetry-coffee-reading-3240766/}{pixabay.com}. The image is completely free and can be used under any circumstance. The cover image size is $1280 \times 1024$. If you would like to change the cover, please crop it according to the size of the cover picture strictly. One free online image clipping site: \href{https://www.fotor.com/cn}{fotor.com}. Feel free to join our QQ Group to get more elegant covers.
+
+\subsection{Logo}
+Aspect ratio of the logo is 1:1 in this guide, i.e. a square picture. To replace the logo, do remember to choose the appropriate picture.
+
+\subsection{Stylized Cover}
+Want to use stylized cover?(For instance, A4-sized PDF designed by Adobe Illustrator) Please comment out \lstinline{\maketitle} and use \lstinline{pdfpages} to insert the cover. Similar for using \lstinline{titlepage}. If you would like to use the cover in version 2.x, please refer to \href{https://github.com/EthanDeng/etitlepage}{etitlepage}.
+
+\section{Chapter Title Display Styles}
+
+This template contains 2 sets of \textit{title display styles},\lstinline{hang}(default) and \lstinline{display} style. For the former, chapter title is displayed on a single line (\lstinline{hang}). For the latter, chapter title is displayed on a double line (\lstinline{display}).In this guide, we use \lstinline{hang} . To change display style, use:
+\begin{lstlisting}
+\documentclass[hang]{elegantbook} %or
+\documentclass[titlestyle=hang]{elegantbook}
+\end{lstlisting}
+
+
+\section{Introduction of Math Environments}
+We defined two sets of theorem modes, \lstinline{simple} style and \lstinline{fancy} style (default). You may change to \lstinline{simple} mode by
+
+\begin{lstlisting}
+\documentclass[simple]{elegantbook} %or
+\documentclass[mode=simple]{elegantbook}
+\end{lstlisting}
+
+In this template, we defined four different theorem class environments
+
+\begin{itemize}
+\item \textit{Theorem Environments}, including title and content, numbering corresponding to chapter. Three types depending on the format:
+   \begin{itemize}
+      \item \textcolor{main}{\textbf{definition}} environment, the color is  \textcolor{main}{main};
+      \item \textcolor{second}{\textbf{theorem, lemma, corollary, axiom, postulate}} environment, the color is \textcolor{second} {second};
+      \item \textcolor{third}{\textbf{proposition}} environment, the color is \textcolor{third}{third}.
+   \end{itemize}
+\item \textit{Example Environment}, including \textbf{example, exercise, problem} environment, auto numbering according to chapter.
+\item \textit{Proof Environment}, including \textbf{proof, note} environment containing introductory symbol (\textbf{note} environment) or ending symbol (\textbf{proof} environment).
+\item \textit{Conclusion Environment}, including \textbf{conclusion, assumption, property, remark and solution}\footnote{We also define an option \lstinline{result}, which can hide the \lstinline{solution} and \lstinline{proof} environments. You can switch between \lstinline{result=answer} and \lstinline{result=noanswer}.} environments, all of which begin with boldfaced words, with format consistent with normal paragraphs.
+\end{itemize}
+
+All of theorem environments have star versions: \textcolor{main}{\textbf{definition*}}, \textcolor{second}{\textbf{theorem*}}, \textcolor{second}{\textbf{lemma*}}, \textcolor{second}{\textbf{corollary*}}, \textcolor{second}{\textbf{axiom*}}, \textcolor{second}{\textbf{postulate*}}, \textcolor{third}{\textbf{proposition*}}. Environments with an asterisk are not numbered.
+
+\subsection{Theorem Class Environments}
+
+\subsubsection{\lstinline{fancy} mode}
+
+In \lstinline{fancy} mode, the template uses the \lstinline{tcolorbox} package to customize the theorem class environments, it is slightly different from the normal theorem environments. The usage is as follows:
+\begin{lstlisting}
+  % name + label
+  \begin{theorem}{theorem name}{label}
+    The content of a theorem with name and label. 
+    Use \ref{thm:label} to refer this theorem.
+  \end{theorem}
+  % no name + label
+  \begin{theorem}{}{label no name}
+    The content of a theorem without name.
+    Use \ref{thm:label no name} to refer this theorem.
+  \end{theorem}
+  % name + no label
+  \begin{theorem}{theorem name}{}
+    The content of a theorem without label.
+    Can't refer this theorem.
+    The last {} can be removed.
+  \end{theorem}
+  % no name + no label
+  \begin{theorem}{}{}
+    The content of a theorem without name and label.
+    Can't refer this theorem.
+    Both of {} can be removed.
+  \end{theorem}
+  \end{lstlisting}
+
+The first parameter \lstinline{theorem name} represents the name of the theorem. If the current theorem has no name, please use \lstinline|{}|\cprotect\footnote{Unless this theorem has neither no label, you should not omit this \verb|{}|.}, and the second parameter \lstinline{label} represents the label used in cross-reference with \verb|\ref{thm:label}|. Note that cross-references must be prefixed with \lstinline{thm:}. 
+
+Other theorem class environments with the same usage includes:
+
+\begin{table}[htbp]
+\centering
+\caption{Theorem Class Environments}
+  \begin{tabular}{llll}
+  \toprule
+  Environment & Label text & Prefix & Cross-reference \\
+  \midrule
+  definition & label & def   & \lstinline|\ref{def:label}| \\
+  theorem & label & thm   & \lstinline|\ref{thm:label}| \\
+  postulate & label & pos & \lstinline|\ref{pos:label}| \\
+  axiom & label & axi & \lstinline|\ref{axi:label}|\\
+  lemma & label & lem   & \lstinline|\ref{lem:label}| \\
+  corrlary & label & cor   & \lstinline|\ref{cor:label}| \\
+  proposition & label & pro   & \lstinline|\ref{pro:label}| \\
+  \bottomrule
+  \end{tabular}%
+\label{tab:theorem-class}%
+\end{table}%
+
+From version 4.1, you can write your theorem environments as follows:
+\begin{lstlisting}
+\begin{theorem}[theorem name]\label{thm:theorem-label}
+  The content of theorem.
+\end{theorem}
+% or
+\begin{theorem}\label{thm:theorem-without-name}
+  The content of theorem.
+\end{theorem}
+\end{lstlisting}
+
+In this case, cross-reference don't have to be prefixed, i.e. the parameter of \lstinline{\ref} is the same as that of \lstinline{\label}.
+ 
+\subsubsection{\lstinline{simple} mode}
+
+In \lstinline{simple} mode, the template uses the \lstinline{amsthm} package to customize the theorem class environments. The usage is as follows:
+
+\begin{lstlisting}
+\begin{theorem}[theorem name]\label{thm:theorem-label}
+  The content of theorem.
+\end{theorem}
+% or 
+\begin{theorem}\label{thm:theorem-without-name}
+  The content of theorem without name.
+\end{theorem}
+\end{lstlisting}
+
+\subsection{Counter for Theorem Environments}
+
+You can use \lstinline{thmcnt} option to control the theorem counter/number display style for the theorem environments, the acceptable options are \lstinline{chapter} (default) and \lstinline{section}:
+
+\begin{lstlisting}
+\documentclass[section]{elegantbook} % turn the Theorem 4.1 to Theorem 4.1.1 
+\documentclass[thmcnt=section]{elegantbook}
+\end{lstlisting}
+
+
+\subsection{Other Customized Environments}
+The other three math environments can be called directly since there are no additional option for them, e.g. \lstinline{example}:
+\begin{lstlisting}
+\begin{example}
+This is the content of example environment.
+\end{example}
+\end{lstlisting}
+
+The effect is as follows:
+
+\begin{example}
+This is the content of example environment.
+\end{example}
+
+These are all similar environments with slight differences lies in:
+
+\begin{itemize}
+   \item Example, exercise, problem environments number within chapter;
+   \item Note begins with introductory symbol and proof ends with ending symbol;
+   \item Conclusion and other environments are normal paragraph environments with boldfaced introductory words.
+\end{itemize}
+
+
+\section{List Environments}
+This template uses \lstinline{tikz} to customize the list environments, with \lstinline{itemize} environment customized to the third depth and \lstinline{enumerate} environment customized to fourth depth. The effect is as follows\\[2ex]
+\begin{minipage}[b]{0.49\textwidth}
+\begin{itemize}
+   \item first item of nesti;
+   \item second item of nesti;
+   \begin{itemize}
+      \item first item of nestii;
+      \item second item of nestii;
+      \begin{itemize}
+         \item first item of nestiii;
+         \item second item of nestiii.
+      \end{itemize}   
+   \end{itemize}
+\end{itemize}
+\end{minipage}
+\begin{minipage}[b]{0.49\textwidth}
+\begin{enumerate}
+   \item first item of nesti;
+   \item second item of nesti;
+   \begin{enumerate}
+      \item first item of nestii;
+      \item second item of nestii;
+      \begin{enumerate}
+         \item first item of nestiii;
+         \item second item of nestiii.
+      \end{enumerate}   
+   \end{enumerate}
+\end{enumerate}
+\end{minipage}
+
+
+\section{Fonts}
+\textcolor{red}{\bfseries Alert} After v3.10, newtx is reset to cm, together with other two options, the \lstinline{math} font option offers:
+\begin{enumerate}
+  \item \lstinline{math=cm}(default), use \LaTeX{} default math font (recommended).
+  \item \lstinline{math=newtx}, use \lstinline{newtxmath} math font (may bring about bugs).
+  \item \lstinline{math=mtpro2}, use \lstinline{mtpro2} package to set math font.
+\end{enumerate}
+
+If you use \lstinline{newtx} fonts, type in:
+\begin{lstlisting}
+\documentclass[math=newtx]{elegantbook}
+\end{lstlisting}
+
+When you are using \lstinline{newtx}, please pay attention to the hyphens. For instance,
+\begin{equation}
+\int_{R^q} f(x,y) dy.\emph{of\kern0pt f} \sin x
+\end{equation}
+
+The corresponding code is: 
+\begin{lstlisting}
+\begin{equation}
+  \int_{R^q} f(x,y) dy.\emph{of \kern0pt f} \sin x
+\end{equation}
+\end{lstlisting}
+
+\subsection{Symbol Fonts}
+Feedback from some 3.08 users claims that error occurs when using our templates with  \lstinline{yhmath}, \lstinline{esvect} and other packages.
+\begin{lstlisting}
+LaTeX Error:
+Too many symbol fonts declared.
+\end{lstlisting}
+
+The reason is that the template redefines font for math so that no new math font is allowed to be added. To use \lstinline{yhmath} and/or \lstinline{esvect}, please locate \lstinline{yhmath} or \lstinline{esvect} in \lstinline{elegantbook.cls}, uncomment corresponding related code.
+
+\begin{lstlisting}
+%%% use yhmath pkg, uncomment following code
+% \let\oldwidering\widering
+% \let\widering\undefined
+% \RequirePackage{yhmath}
+% \let\widering\oldwidering
+
+%%% use esvect pkg, uncomment following code
+% \RequirePackage{esvect}
+\end{lstlisting}
+
+\section{Bibliography}
+
+This template uses biblatex to generate the bibliography, the default citestyle and bibliography style are both \lstinline{numeric}. Let's take a glance at the citation effect. ~\cite{en1} use data from a major peer-to-peer lending \cite{en3} marketplace in China to study whether female and male investors evaluate loan performance differently \parencite{en2}. 
+
+If you want to use biblatex, you must create a file named \lstinline{reference.bib}, add bib items (from Google Scholar, Mendeley, EndNote, and etc.) to \lstinline{reference.bib} file, then cite the bibkey in the \lstinline{tex} file. The biber will automatically generate the bibliography for the reference you cited.
+
+In order to get the editors' auto-completion working, you need to add following code in your preamble:
+
+\begin{lstlisting}
+  \addbibresource[location=local]{reference.bib}
+\end{lstlisting}
+
+Then include the print commands where you want to print the bibliography:
+\begin{lstlisting}
+  \printbibliography[heading=bibintoc, title=\ebibname]
+\end{lstlisting}
+
+
+
+
+To change the bibliography style, this version introduces two options: \lstinline{citestyle} and \lstinline{bibstyle}, please refer to \href{https://ctan.org/pkg/biblatex}{CTAN:biblatex} for more detail about these options. You can change your bibliography style as
+
+\begin{lstlisting}
+\documentclass[citestyle=numeric-comp, bibstyle=authoryear]{elegantbook} 
+\end{lstlisting}
+
+We also add the \lstinline{bibend} option to this template, you can choose \lstinline{biber} (default) or \lstinline{bibtex} as you like, \lstinline{biber} is recommended.
+
+\begin{lstlisting}
+\documentclass[bibtex]{elegantbook} % or
+\documentclass[bibend=bibtex]{elegantbook}
+\end{lstlisting}
+
+\section{Preface}
+
+If you want to add a preface before the first chapter with the number of chapter unchanged, please add the preface in the following way:
+\begin{lstlisting}
+\chapter*{Introduction}
+\markboth{Introduction}{Introduction}
+The content of introduction.
+\end{lstlisting}
+
+\section{Content Option and Depth}
+Option for content \lstinline{toc}, you can  choose either one column(\lstinline{onecol}) or two columns(\lstinline{twocol}). For two columns:
+\begin{lstlisting}
+\documentclass[twocol]{elegantbook}
+\documentclass[toc=twocol]{elegantbook}
+\end{lstlisting}
+
+Default content depth is 1, use to use \lstinline|\setcounter{tocdepth}{2}|.
+
+\section{Introduction Environment}
+We create a introduction environment to display the structure of chapter. The basic useage is as follows:
+\begin{lstlisting}
+\begin{introduction}
+  \item Definition of Theorem
+  \item Ask for help
+  \item Optimization Problem
+  \item Property of Cauchy Series
+  \item Angle of Corner
+\end{introduction}
+\end{lstlisting}
+And you will get:
+\begin{introduction}
+  \item Definition of Theorem
+  \item Ask for help
+  \item Optimization Problem
+  \item Property of Cauchy Series
+  \item Angle of Corner
+\end{introduction}
+
+You can change the title of this environment by modifying the optional argument of this environment:
+\begin{lstlisting}
+\begin{introduction}[Brief Introduction]
+...
+\end{introduction}
+\end{lstlisting}
+
+%\section{Problem Set}
+The environment \lstinline{problemset} is used at the end of each chapter to display corresponding exercises. Just type in the following sentences:
+\begin{lstlisting}
+\begin{problemset}
+  \item exercise 1
+  \item exercise 2
+  \item exercise 3
+\end{problemset}
+\end{lstlisting}
+And you will get:
+\begin{problemset}
+  \item exercise 1
+  \item exercise 2
+  \item exercise 3
+  \item math equation test:
+  \begin{equation}
+  a^2+b^2=c_{2_{i}} (1,2) [1,23]
+  \end{equation}
+\end{problemset}
+\begin{remark}
+If you want to customize the title of \lstinline{problemset}, please change the optional argument like in introduction environment. In this version the \lstinline{problemset} environment automatically appears in the table of contents but not in the header or footer(to be fixed).
+\end{remark}
+
+\begin{solution}
+  If you want to customize the title of \lstinline{problemset}, please change the optional argument like in introduction environment. In this version the \lstinline{problemset} environment automatically appears in the table of contents but not in the header or footer(to be fixed).
+\end{solution}
+
+\section{Margin Notes}
+In 3.08, we introduced \lstinline{marginpar=margintrue} and \lstinline{\elegantpar} (Beta) with piles of bugs. Hence we decide to remove them in 3.09 and will suspend the options till revolutionary optimization. Sorry for all the bugs! However, we retain the option \lstinline{marginpar} for users to get margin motes by activating \lstinline{marginpar=margintrue} and using \lstinline{\marginpar} or \lstinline{marginnote} packages.
+
+\begin{remark}
+Note that text and equation are both available in the margin notes.
+\begin{lstlisting}
+% text
+\marginpar{margin paragraph text}
+
+% equation
+\marginpar{
+\begin{equation}
+  a^2 + b^2 = c^2
+\end{equation}
+}
+\end{lstlisting}
+
+For tables and figures, note that floating environment is not allowed. You have to use \lstinline{includegraphics} or \lstinline{table} and use \lstinline{\captionof} to name it. To get centralized figures or tables, use \lstinline{\centerline} or \lstinline{center}. To learn more, please refer to \href{https://tex.stackexchange.com/questions/5583/caption-of-figure-in-marginpar-and-caption-of-wrapfigure-in-margin}{Caption of Figure in Marginpar}.
+
+\begin{lstlisting}
+% graph with centerline command
+\marginpar{
+  \centerline{
+    \includegraphics[width=0.2\textwidth]{logo.png}
+  }
+  \captionof{figure}{your figure caption}
+}
+
+% graph with center environment
+\marginpar{
+  \begin{center}
+    \includegraphics[width=0.2\textwidth]{logo.png}
+    \captionof{figure}{your figure caption}
+  \end{center}
+}
+\end{lstlisting}
+
+\end{remark}
+
+
+
+\chapter{ElegantBook Writing Sample}
+
+\begin{introduction}
+\item Theorem Class Envrionments
+\item Cross Reference
+\item Math Environments
+\item List Environments
+\item Logo and Base 
+\item $a^2+b^2=c^2$
+\end{introduction}
+
+
+\lipsum[1]
+% source: https://www.maths.tcd.ie/~dwilkins/LaTeXPrimer/Theorems.html
+
+\section{Writing Sample}
+
+We will define the integral of a measurable function in three steps. First, we define the integral of a nonnegative simple function. Let $E$ be the measurable set in $\mathcal{R}^N$.
+
+\begin{definition}[Left Coset]
+Let $H$ be a subgroup of a group~$G$.  A \emph{left coset} of $H$ in $G$ is a subset of $G$ that is of the form $xH$, where $x \in G$ and $xH = \{ xh : h \in H \}$. Similarly a \emph{right coset} of $H$ in $G$ is a subset of $G$ that is of the form $Hx$, where $Hx = \{ hx : h \in H \} \hbar$ 
+\end{definition}
+
+\begin{note}
+Note that a subgroup~$H$ of a group $G$ is itself a left coset of $H$ in $G$.
+\end{note}
+
+\lipsum[2]
+
+\begin{theorem}[Lagrange's Theorem] \label{thm:lg}
+Let $G$ be a finite group, and let $H$ be a subgroup of $G$. Then the order of $H$ divides the order of $G$.
+\end{theorem}
+
+As theorem \ref{thm:lg} refered.
+
+\lipsum[3]
+
+
+\begin{theorem}{theorem name}{label text}
+  The content of theorem.
+\end{theorem}
+
+we can refer this theorem as \ref{thm:label text}.
+
+
+\begin{proposition}[Size of Left Coset]
+Let $H$ be a finite subgroup of a group $G$.  Then each left coset of $H$ in $G$ has the same number of elements as $H$.
+\end{proposition}
+
+\begin{proof}
+  Let $z$ be some element of $xH \cap yH$. Then $z = xa$ for some $a \in H$, and $z = yb$ for some $b \in H$. If $h$ is any element of $H$ then $ah \in H$ and $a^{-1}h \in H$, since $H$ is a subgroup of $G$. But $zh = x(ah)$ and $xh = z(a^{-1}h)$ for all $h \in H$. Therefore $zH \subset xH$ and $xH \subset zH$, and thus $xH = zH$.  Similarly $yH = zH$, and thus $xH = yH$, as required. 
+\end{proof}
+
+\begin{figure}[htbp]
+  \centering
+  \includegraphics[width=0.6\textwidth]{scatter.jpg}
+  \caption{Matplotlib: Scatter Plot Example\label{fig:scatter}}
+\end{figure}
+
+Regression analysis is a powerful statistical method that allows you to examine the relationship between two or more variables of interest. While there are many types of regression analysis, at their core they all examine the influence of one or more independent variables on a dependent variable. The process of performing a regression allows you to confidently determine which factors matter most, which factors can be ignored, and how these factors influence each other.
+
+Let's continue using our application training example. In this case, we'd want to measure the historical levels of satisfaction with the events from the past three years or so, as well as any information possible in regards to the independent variables. 
+
+\section{Second section}
+This second section\index{S!section} may include some special word, 
+and expand the ones already used\index{keywords!used}.
+
+
+\begin{table}[htbp]
+  \small
+  \centering
+  \caption{Auto MPG and Price \label{tab:reg}}
+    \begin{tabular}{lcc}
+    \toprule
+                    &       (1)         &        (2)      \\
+    \midrule
+    mpg             &    -238.90***     &      -49.51     \\
+                    &     (53.08)       &      (86.16)    \\
+    weight          &                   &      1.75***    \\
+                    &                   &      (0.641)    \\
+    constant        &     11,253***     &       1,946     \\
+                    &     (1,171)       &      (3,597)   \\
+    obs             &        74         &         74     \\
+    $R^2$           &      0.220        &       0.293    \\
+    \bottomrule
+    \multicolumn{3}{l}{\scriptsize Standard errors in parentheses} \\
+    \multicolumn{3}{l}{\scriptsize *** p<0.01, ** p<0.05, * p<0.1} \\
+    \end{tabular}%
+\end{table}%
+
+\lipsum[1-2]
+
+\begin{itemize}
+  \item Routing and resource discovery;
+       \begin{itemize} 
+             \item Language Models
+            \item Vector Space Models
+         \end{itemize}
+  \item Resilient and scalable computer networks;
+  \item Distributed storage and search.
+\end{itemize}
+
+%\problemset
+\begin{problemset}
+  \item Solve the equation $5(- 3x - 2) - (x - 3) = -4(4x + 5) + 13$.
+  \item Find the distance between the points $(-4 , -5)$ and $(-1 , -1)$.
+  \item Find the slope of the line $5x - 5y = 7$.
+\end{problemset}
+
+
+\chapter{FAQ}
+We list some FAQs for users to refer to:
+\begin{enumerate}
+  \item \question{Why option numbers for natbib fail to take effect in v3.07?}
+  In v3.07, when \lstinline{gbt7714} is introduced, option \lstinline{authoryear} is incompatible with \lstinline{natbib}. In v3.08 and 3.09, \lstinline{numbers}, \lstinline{numbers}, \lstinline{super} and \lstinline{authoryear} are introduced.
+  \item \question{I want to customize font and background color.}
+  Please use \lstinline{pagecolor} to change background color, refer to \href{https://tex.stackexchange.com/questions/278544/xcolor-what-is-the-equivalent-of-default-text-color}{this} to customize font.
+  \item \question{Which version should I choose?}
+  Please use \href{https://github.com/ElegantLaTeX/ElegantBook/releases}{Latest Release} via GitHub or \TeX{} Live 2022.
+  \item \question{Which editor should I choose?}
+  You can use \TeX{} Live 2022 built-in \TeX works or \TeX Studio. You may refer to \href{https://github.com/EthanDeng/texworks-autocomplete}{\TeX{}works autocomplete}. \TeX{} Live 2022 + \TeX{}studio is strongly recommended. Related configurations can be found at \href{https://github.com/EthanDeng/vscode-latex}{vscode-latex} and \href{https://github.com/EthanDeng/sublime-text-latex}{sublime-text-latex}.
+  \item \question{Hello, we want to use ElegantBook to write a book about machine learning and would like your authorization.}
+  Feel free to use our templates by pointing out our copyright. For other issues, please refer to LPPL-1.3c. If you want to show us your work, you can share the URL with us afterwards.
+  \item \question{What is cross reference?}
+  This template is aimed at who are not a complete beginner for \LaTeX{}. Please learn more about \LaTeX{} before using this template.
+  \item \question{Is the language for code highlighting optional?}
+  Yes, \lstinline{listings} package is used in ElegantBook, hence language is optional(e.g. \lstinline{language=Python}). For global setting, use \lstinline{lstset}. For more information, please refer to package documentations.
+  \item \question{When will Beamer template (ElegantSlide or ElegantBeamer) forthcoming?}
+  Since there is an excellent theme \href{https://github.com/matze/mtheme}{Metropolis}, no plan for Beamer theme.
+\end{enumerate}
+
+\chapter{Version History}
+We revised our templates now and then. This section shows the version story of ElegantBook.
+
+
+\datechange{2022/08/15}{release of v4.4.}
+
+\begin{change}
+  \item Add custome theorem definition command \lstinline{\elegantnewtheorem};
+  \item Fix star environment(*) for inner environments (\href{https://github.com/ElegantLaTeX/ElegantBook/issues/167}{issue \#167});
+  \item Change English fonts from TeX Gyre Termes to TeX Gyre TermesX;
+  \item Re-construct some theorem environments to enchance compatibility;
+  \item Remove Gitee repo due the privacy policy;
+  \item Re-open Github pull requests.
+\end{change}
+
+
+
+
+\datechange{2022/04/09}{release of v4.3.}
+
+\begin{change}
+  \item Remove part newtx settings, set TeX Gyre Termes/Heros fonts under \hologo{XeLaTeX}.
+  \item Fix Chinese fonts in the theorem environments.
+  \item Add theorem counter option, \lstinline{thmcnt=section}.
+  \item Add bib option \lstinline{bibend}, which can take value of biber and bibtex.
+  \item \textbf{! Warnings}: The multilingual option may cause some unexpected errors, you can report in this \href{https://github.com/ElegantLaTeX/ElegantBook/issues/170}{issue}.
+\end{change}
+
+
+
+\datechange{2022/03/08}{release of v4.2.}
+
+\begin{change}
+  \item Bug fix due to the update of newtx fonts;
+  \item Add `Chapter' in TOC, and redefine \lstinline{\chaptername} to unify the logic under different languages;
+  \item Add language option for Japanese, \lstinline{lang=jp}.
+\end{change}
+
+
+\datechange{2021/05/02}{release of v4.1.}
+
+\begin{change}
+  \item \textbf{! Big Change}: Change the bibliography method from \hologo{BibTeX} to biblatex(with backend  \lstinline{biber});
+  \item \textbf{! Big Change}: Add support for the default theorem writing method (with optional name and label);
+  \item Add left and right space;
+  \item Support hyperlink from the text of TOC;
+  \item Remove the \hologo{pdfLaTeX} compatiblity check for Chinese.
+  \item Add multilingual support, for french \lstinline{lang=fr}, dutch \lstinline{lang=nl}, Hungarian  \lstinline{lang=hu}, Spanish \lstinline{lang=es}, Mongolian \lstinline{lang=mn} etc.
+\end{change}
+
+\datechange{2020/04/12}{release of v3.11, \textcolor{red}{\textbf{LAST} version of 3.x}.}
+
+
+\begin{change}
+  \item \textbf{! Fix}: Fix \lstinline{natbib option clash} problems caused by \lstinline{gbt7714} updates.
+  \item Remove \lstinline{base} decorations and its options since \lstinline{pgfornament} package is not included in \TeX{} Live 2020.
+  \item Fix spacing problem in some environments.
+  \item Introduce language option for Italian, \lstinline{lang=it}.
+\end{change}
+
+
+\datechange{2020/02/10}{release of v3.10}
+
+\begin{change}
+  \item Introduce \lstinline{math} for math font, optional styles are \lstinline{newtx} and \lstinline{cm}.\\
+  \textbf{Notice}: The math font \lstinline{newtxmath} in previous versions is reset to default \LaTeX{} math font, to keep previous math font, please declare \lstinline{math=newtx}.
+  \item Introduce \lstinline{chinesefont} option, with \lstinline{founder}, \lstinline{ctexfont} and \lstinline{nofont} available.
+  \item Turn author information on the cover optional and add customized command \lstinline{\bioinfo}.
+  \item Add version history with command \lstinline{\datechange} and environment \lstinline{change}.
+  \item Add Chinese chapter style \lstinline{scheme} with option \lstinline{chinese}.
+  \item Since the bug raised by \lstinline{\lvert} is fixed, exchange package positions of \lstinline{ctex} and \lstinline{amsmath}.
+  \item Drop \lstinline{\lastpage} from header to avoid page anchor bug and adding \lstinline{\frontmatter}.
+  \item Revise bibliography option \lstinline{cite} with optional styles \lstinline{numbers},\lstinline{authoryear} and \lstinline{super}.
+  \item Introduce bibliography style option \lstinline{bibstyle}, with default bib style \lstinline{apalike} for English mode and \lstinline{gbt7714} package for Chinese mode.
+\end{change}
+
+\datechange{2019/08/18}{release of v3.09}
+
+\begin{change}
+  \item Remove \lstinline{\elegantpar} temporary and remind users to use \lstinline{\marginnote} and \lstinline{\marginpar} instead.
+  \item Use \lstinline{esint} to display integral operator.
+  \item Add new command \lstinline{toc}, with options  \lstinline{onecol} and \lstinline{twocol}.
+  \item Add new option \lstinline{cite} \lstinline{super} for superscript-displayed citation.
+  \item Revise \lstinline{problemset}.
+\end{change}
+
+
+\nocite{en2,en3}
+
+\printbibliography[heading=bibintoc, title=\ebibname]
+\appendix
+
+
+\chapter{Mathematical Tools}
+
+This appendix covers some of the basic mathematics used in econometrics. We briefly discuss the properties of summation operators, study the properties of linear and some nonlinear equations, and review the ratios and percentages. We also introduce some special functions that are common in econometrics applications, including quadratic functions and natural logarithms. The first four sections require only basic algebraic techniques. The fifth section briefly reviews differential Calculus Although Calculus is not necessary to understand much of this book, it is used in some of the end-of-chapter appendices and in some of the more advanced topics in part 3.
+
+\section{Summation Operator and Description Statistics}
+
+\textbf{Summation Operator} is an abbreviation used to express the summation of numbers, it plays an important role in statistics and econometrics analysis. If $\{x_i: i=1, 2, \ldots, n\}$ is a sequence of $n$ numbers, the summation of the $n$ numbers is:
+
+\begin{equation}
+\sum_{i=1}^n x_i \equiv x_1 + x_2 +\cdots + x_n
+\end{equation}
+
+
+\end{document}

guide.tex

@@ -1,266 +0,0 @@
-\documentclass{elegantbook}
-
-\author{ddswhu \& Liam Huang}
-\email{ddswhu@outlook.com}
-
-\zhtitle{优美的 \LaTeX{} 书籍}
-\zhend{模板}
-\entitle{Elegant\LaTeX{} Book}
-\enend{Template}
-\version{3.01}
-\myquote{Victory won\rq t come to us unless we go to it.}
-\logo{logo.png}
-\cover{cover.pdf}
-
-%green color
-   \definecolor{main1}{RGB}{0,120,2}
-   \definecolor{second1}{RGB}{230,90,7}
-   \definecolor{third1}{RGB}{0,160,152}
-%cyan color
-   \definecolor{main2}{RGB}{0,175,152}
-   \definecolor{second2}{RGB}{239,126,30}
-   \definecolor{third2}{RGB}{120,8,13}
-%blue color
-   \definecolor{main3}{RGB}{20,50,104}
-   \definecolor{second3}{RGB}{180,50,131}
-   \definecolor{third3}{RGB}{7,127,128}
-
-\usepackage{makecell}
-\usepackage{lipsum}
-\usepackage{texnames}
-
-
-
-\begin{document}
-\maketitle
-\tableofcontents
-\mainmatter
-\chapter{Elegant\LaTeX{} 系列模板介绍}
-
-值此版本发行之际，我们 Elegant\LaTeX{} 项目组向大家重新介绍一下我们的工作，我们致力于打造一系列美观、优雅、简便的模板方便用户使用。Elegant\LaTeX{} 系列模板目前由 ElegantNote，ElegantBook，ElegantPaper，ElegantBeamer 组成，分别用于排版笔记，书籍，工作论文和幻灯片讲稿。这些子项目的名词是一体的，请在使用这些名词的时候不要将其断开（如 Elegant Note 是不正确的写法）。并且，Elegant\LaTeX{}  Book 指的即是 ElegantBook。
-
-请用户在作者的主页下载最新版本，下载地址：\href{https://ddswhu.me/resource/}{https://ddswhu.me/resource/}。本文将介绍本模板的一些设置内容以及基本使用方法。如果您在使用此模板，欢迎把您使用此模板制作的成品发一份给我们，谢谢！如果您有其他问题，建议或者意见，欢迎联系我：\mailto{ddswhu@outlook.com}。
-
-
-\section{ElegantBook 更新说明}
-在这几年间，我们收到了很多用户的反馈，主要的问题涉及到字体安装，编码支持，定理浮动，定理跨页，交叉引用等等。我们思前想后，原先让用户安装字体以追求视觉上的美观并不完美，用户陷入了巨大的麻烦，这违背了我们的模板初衷。因此我们在新版中删除了这部分，用户无需安装任何字体。让我们来看下此次 ElegantBook 模板 3.0 更新的主要内容有：
-
-\begin{enumerate}[noitemsep]
-   \item 删除了自定义字体设置，改用 \texttt{ctex} 宏包用以支持中文。
-   \item 使用 \texttt{tcolorbox} 宏包改写了原先的定理类环境，目前定理环境等均可以跨页。
-   \item 重新命名了定理类环境的名称（theorem，definition，proposition 等）。
-   \item 重新命名了颜色的名字（first，second，third）。
-\end{enumerate}
-
-\section{未来更新计划}
-
-
-\begin{enumerate}[noitemsep]
-   \item 设计一个适合的 LOGO；
-   \item 重新设计 base 图标；
-   \item 重新设计一个好看的封面。
-   \item 将基础模板改为英文模板，添加选项使其支持中文。
-   \item 将最早的 ElegantNote 重新设计为简版发布。
-   \item 添加一个简化风格（plain）的颜色主题。
-\end{enumerate}
-
-\chapter{ElegantBook 设置说明}
-
-
-\section{编译方式}
-
-本模板基于基础的 book 文类，所以 book 的选项对于本模板也是有效的。默认编码为 UTF-8，推荐使用 \TeX{} Live 编译。作者编写环境为 Win10(64bit) + \TeX{} Live 2018。由于使用的是 \texttt{ctex} 宏包，所以支持 \texttt{pdflatex} 以及 \texttt{xelatex} 编译。
-
-
-\section{选项设置}
-本文特殊选项设置共有 2 类，分为 {\color{main}主题颜色}设置 以及 {\color{main}章标题显示风格}设置。
-
-第 1 类为{\color{main}主题颜色}设置，内置 3 组颜色主题，分别为 \verb|green|（默认），\verb|cyan|，\verb|blue|，另外还有一个自定义的选项 \verb|nocolor|，用户\textbf{必须}在使用模板的时候选择某个颜色主题或选择 \verb|nocolor| 选项。调用颜色主题 \verb|green| 的方法为 \verb|\documentclass[green]{elegantbook}|或者使用 \verb|\documentclass[color=green]{elegantbook}|。需要改变颜色的话请选择 \verb|nocolor| 选项或者使用 \verb|color=none|，然后在导言区定义 main、second、third 颜色，具体的方法如下：
-\begin{verbatim}
-\definecolor{main}{RGB}{70,70,70}    %定义 main 颜色值
-\definecolor{second}{RGB}{115,45,2}    %定义 second 颜色值
-\definecolor{third}{RGB}{0,80,80}     %定义 third 颜色值
-\end{verbatim}
-
-\begin{table}[htp]
-\centering
-\begin{tabular}{ccccc}
-\toprule
-	  & green & cyan & blue & 主要使用的环境\\
-\midrule
-main & \makecell{{\color{main1}\rule{1cm}{1cm}}}& \makecell{{\color{main2}\rule{1cm}{1cm}}}&\makecell{ {\color{main3}\rule{1cm}{1cm}}}& definition \\
-
-second &\makecell{ {\color{second1}\rule{1cm}{1cm}}}& \makecell{{\color{second2}\rule{1cm}{1cm}}}&\makecell{ {\color{second3}\rule{1cm}{1cm}}}&theorem \ lemma \ corollary\\
-
-third &\makecell{ {\color{third1}\rule{1cm}{1cm}}}& \makecell{{\color{third2}\rule{1cm}{1cm}}}&\makecell{ {\color{third3}\rule{1cm}{1cm}}}&proposition\\
-\bottomrule
-\end{tabular}
-\caption{ElegantBook 模板中的三套颜色主题\label{tab:color thm}}
-\end{table}
-
-第 2 类为{\color{main} 章标题显示风格}，包含 \verb|hang|（默认）与 \verb|display| 两种风格，区别在于章标题单行显示（\verb|hang|）与双行显示（\verb|display|），本说明使用了 \verb|hang|。调用方式为 \verb|\documentclass[hang]{elegantbook}| 或者 \verb|\documentclass[titlestyle=hang]{elegantbook}|。
-
-综合起来，同时调用三个选项使用 \verb|\documentclass[color=X,titlestyle=Y]{elegantbook}|。其中 \verb|X| 可以选择 \verb|green|,\verb|cyan|,\verb|blue|,\verb|none|；\verb|Z| 可以选择 \verb|hang| 或者 \verb|display|。
-
-\section{数学环境简介}
-
-在我们这个模板中，定义了三大类环境
-
-\begin{enumerate}[noitemsep]
-\item 定理类环境，包含标题和内容两部分。根据格式的不同分为3种
-   \begin{itemize}[noitemsep]
-      \item {\color{main}\bfseries definition} 环境，含有一个可选项，编号以章节为单位，颜色为 {\color{main}main}；
-      \item {\color{second}\bfseries theorem、lemma、corollary} 环境，颜色为主颜色 {\color{second}second}，编号均以章节为单位；
-      \item {\color{third}\bfseries proposition} 环境，含有一个可选项，编号以章节为单位，颜色为 {\color{third}{third}}。
-   \end{itemize}
-\item 示例类环境，有 \textbf{example、exercise} 环境，自动编号，编号以章节为单位。
-\item 证明类环境，有 \textbf{proof、note} 环境，特点是，有引导符或者结尾符，\textbf{note} 环境有引导符号，\textbf{proof} 环境有证明完毕标志。
-\item 结论类环境，有\textbf{conclusion、assumption、property，remark、solution} 环境，三者均以粗体的引导词为开头，和普通段落格式一致。
-\end{enumerate}
-
-\section{可编辑的字段}
-在模板中，可以编辑的字段分别为作者 \verb|\author|、邮箱 \verb|\email|、中文标题 \verb|\zhtitle|、中文标题结尾 \verb|\zhend|、英文标题\verb| \entitle|、英文标题结尾 \verb|\enend|、名言 \verb|\myquote|、版本号 \verb|\version|。并且，可以根据自己的喜好把封面水印效果的 \verb|cover.pdf| 替换掉，以及封面中用到的 \verb|logo.png|。
-
-\chapter{ElegantBook 写作示例}
-
-\section{Economics and Differentiable Function}
-
-Economics focuses on the behaviour and interactions of economic agents and how economies work. Microeconomics analyzes basic elements in the economy, including individual agents and markets, their interactions, and the outcomes of interactions. Individual agents may include, for example, households, firms, buyers, and sellers. Macroeconomics analyzes the entire economy (meaning aggregated production, consumption, savings, and investment) and issues affecting it, including unemployment of resources (labour, capital, and land), inflation, economic growth, and the public policies that address these issues (monetary, fiscal, and other policies). See glossary of economics.
-\begin{align*}
-   &\max(\min)\quad \mathbb{E}\int_{t_0}^{t_1}f(t,x,u)\,dt\\
-   &\quad\mbox{s.t.} \quad dx=g(t,x,u)dt+\sigma(t,x,u)dz\\
-   &\quad \hspace{2.em} k(0)=k_0\;\text{given}
-\end{align*}
-
-where $z$ is stochastic process or white noise or wiener process.
-
-Other broad distinctions within economics include those between positive economics, describing "what is", and normative economics, advocating "what ought to be"; between economic theory and applied economics; between rational and behavioural economics; and between mainstream economics and heterodox economics.
-
-Economic analysis can be applied throughout society, in business, finance, health care, and government. Economic analysis is sometimes also applied to such diverse subjects as crime, education, the family, law, politics, religion, social institutions, war, science, and the environment.
-
-\begin{definition}{Differenzierbarkeit}{diff}
-Eine Funktion $f:~I\to\mathbb{R}$ auf einem Intervall $I$ hei\ss{}t in $x_0\in I$ differenzierbar oder linear approximierbar, wenn der Grenzwert
-   \begin{equation*}
-      \lim\limits_{x\to x_0}\frac{f(x)-f(x_0)}{x-x_0}=
-      \lim\limits_{h\to 0}\frac{f(x_0+h)-f(x_0)}{h}
-   \end{equation*}
-existiert. Bei Existenz hei\ss{}t dieser Grenzwert Ableitung oder Differentialquotient von $f$ in $x_0$ und man schreibt f\"{u}r ihn
-   \begin{equation*}
-      f'(x_0)\quad\text{oder}\quad\frac{df}{dx}(x_0).
-   \end{equation*}
-\end{definition}
-
-The discipline was renamed in the late 19th century, primarily due to Alfred Marshall, from "political economy" to "economics" as a shorter term for "economic science". At that time, it became more open to rigorous thinking and made increased use of mathematics, which helped support efforts to have it accepted as a science and as a separate discipline outside of political science and other social sciences.
-
-\begin{example}
-$E$ and $F$ be two events such that $P(E)=
-P(F)=1/2$, and $P(E\cap F)=1/3$, let $\mathscr{F}=\sigma(Y)$,  $X$ and $Y$ be the indicate function of $E$ and $F$ respectively. How to compute $\mathbb{E}[ X\mid \mathscr{F} ]$?
-\end{example}
-
-Some subsequent comments criticized the definition as overly broad in failing to limit its subject matter to analysis of markets. From the 1960s, however, such comments abated as the economic theory of maximizing behaviour and rational-choice modelling expanded the domain of the subject to areas previously treated in other fields. There are other criticisms as well, such as in scarcity not accounting for the macroeconomics of high unemployment.
-
-\begin{exercise}
-let $S=l^\infty=\big\{(x_n)\mid \exists\, M \text{ such that } \forall n, |x_n|\leq M,x_n\in \mathbb{R}\big\}$, $\rho_{\infty}(x,y)=\sup\limits_{n\geq 1}|x_n-y_n|$, show that $\big(l^\infty,\rho_{\infty}\big)$ is complete.
-\end{exercise}
-
-\begin{theorem}{Mittelwertsatz f\"{u}r $n$ Variable}{31}
-Es sei $n\in\mathbb{N}$, $D\subseteq\mathbb{R}^n$ eine offene Menge und $f\in C^{1}(D,\mathbb{R})$. Dann gibt es auf jeder Strecke $[x_0,x]\subset D$ einen Punkt $\xi\in[x_0,x]$, so dass gilt
-\begin{equation*}
-   f(x)-f(x_0) = \operatorname{grad} f(\xi)^{\top}(x-x_0)
-\end{equation*}
-\end{theorem}
-
-\begin{note}
-在本模板中，引理（lemma），推论（corollary ）的样式和定理的样式一致，包括颜色，仅仅只有计数器的设置不一样。
-\end{note}
-
-
-Gary Becker, a contributor to the expansion of economics into new areas, describes the approach he favours as "combin[ing the] assumptions of maximizing behaviour, stable preferences, and market equilibrium, used relentlessly and unflinchingly."One commentary characterizes the remark as making economics an approach rather than a subject matter but with great specificity as to the "choice process and the type of social interaction that [such] analysis involves." 
-
-
-Economic efficiency measures how well a system generates desired output with a given set of inputs and available technology. Efficiency is improved if more output is generated without changing inputs, or in other words, the amount of "waste" is reduced. A widely accepted general standard is Pareto efficiency, which is reached when no further change can make someone better off without making someone else worse off.
-
-\begin{proposition}{最优性原理}{max}
-如果 $u^*$ 在 $[s,T]$ 上为最优解，则 $u^*$在$[s,T]$ 任意子区间都是最优解，假设区间为 $[t_0,t_1]$ 的最优解为 $u^*$ ，则 $u(t_0)=u^{*}(t_0)$，即初始条件必须还是在 $u^*$ 上。
-\end{proposition}
-
-Microeconomics examines how entities, forming a market structure, interact within a market to create a market system. These entities include private and public players with various classifications, typically operating under scarcity of tradable units and light government regulation. The item traded may be a tangible product such as apples or a service such as repair services, legal counsel, or entertainment.
-
-\begin{corollary}{}{}
-假设 $V(\cdot,\cdot)$ 为值函数，则根据最大值原理~\ref{thm:31}，有如下推论
-\[
-V(k,z)=\max\Big\{u\big(zf(k)-y\big)+\beta \mathbb{E}V(y,z^\prime)\Big\}
-\]
-\end{corollary}
-
-\begin{proof}
-因为 $y^*=\alpha\beta z k^\alpha$，$V(k,z)=\alpha/1-\alpha\beta\ln k_0+1/1-\alpha\beta \ln z_0+\Delta$。
-   \begin{align*}
-   \text{右边}&=\Big\{u\big(zf(k)-y\big)+\beta \mathbb{E}V(y,z^\prime)\Big\}\\
-   &=\ln(zk^\alpha-\alpha\beta zk^\alpha)+\beta\mathbb{E}\Big[\frac{\alpha}{1-\alpha\beta}\ln y+\frac{1}{1-\alpha\beta}\ln z^\prime+\Delta\Big]\\
-   &=\ln(1-\alpha\beta)zk^\alpha+\beta\Big\{\mathbb{E}\big[\frac{\alpha}{1-\alpha\beta}\ln \alpha\beta z k^\alpha\big]+\frac{1}{1-\alpha\beta}\mathbb{E}[\ln z^\prime]+\Delta\Big\}
-   \end{align*}
-利用 $\mathbb{E}[\ln z^\prime]=0$，并将对数展开得
-   \begin{align*}
-   \text{右边}&=\ln (1-\alpha\beta)+\ln z+\alpha\ln k+\frac{\alpha\beta}{1-\alpha\beta}\big[\ln \alpha\beta+\ln z+\alpha\ln k\big]+\frac{\beta}{1-\alpha\beta}\mu+\beta \Delta\\
-   &=\frac{\alpha}{1-\alpha\beta}\ln k+\frac{1}{1-\alpha\beta}\ln z+\Delta
-   \end{align*}
-所以 $\text{左边}=\text{右边}$，证毕。
-\end{proof}
-
-
-
-\begin{property}
-Properties of Cauchy Sequence
-\begin{enumerate}[noitemsep]
-\item $\{x_k\}$ is cauchy sequence then $\{x_k^i\}$ is cauchy sequence.
-\item $x_k\in \mathbb{R}^n$, $\rho(x,y)$ is Euclidean, then cauchy is equivalent to convergent, $(\mathbb{R}^n,\rho)$ metric space is complete.
-\end{enumerate}
-\end{property}
-
-\begin{note}
-conclusion、assumption、property，remark、solution 的环境效果是一样的。
-\end{note}
-
-Various market structures exist. In perfectly competitive markets, no participants are large enough to have the market power to set the price of a homogeneous product. In other words, every participant is a "price taker" as no participant influences the price of a product. In the real world, markets often experience imperfect competition.
-
-Scarcity is represented in the figure by people being willing but unable in the aggregate to consume beyond the PPF (such as at $X$) and by the negative slope of the curve.[32] If production of one good increases along the curve, production of the other good decreases, an inverse relationship. This is because increasing output of one good requires transferring inputs to it from production of the other good, decreasing the latter.
-
-\begin{figure}[!htbp]
-	\centering
-	\includegraphics[width=0.6\textwidth]{mpg.png}
-	\caption{The Relationship between MPG and Weight\label{fig:mpg}}
-\end{figure}
-
-\begin{definition}{Contraction mapping}{mapping}
-$(S,\rho)$ is the metric space, $T: S\to S$, If there exists $\alpha\in(0,1)$ such that for any $x$ and $y\in S$, the distance
-\begin{equation}
-\rho(Tx,Ty)\leq \alpha\rho(x,y)
-\end{equation}
-Then $T$ is a {\color{main} contraction mapping}.
-\end{definition}
-
-\begin{remark}
-\begin{enumerate}[noitemsep]
-\item $T:S\to S$, where $S$ is a metric space, if  for any $x,y\in S$, $\rho(Tx,Ty)<\rho(x,y)$ is not contraction mapping.
-\item Contraction mapping is continuous map.
-\end{enumerate}
-\end{remark}
-
-
-\begin{conclusion}
-In theory, in a free market the aggregates (sum of) of quantity demanded by buyers and quantity supplied by sellers may reach economic equilibrium over time in reaction to price changes; in practice, various issues may prevent equilibrium, and any equilibrium reached may not necessarily be morally equitable. For example, if the supply of healthcare services is limited by external factors, the equilibrium price may be unaffordable for many who desire it but cannot pay for it.
-\end{conclusion}
-
-\section{Bibliography}
-This template uses Bib\TeX{} to generate the bibliography, the default bibliography style is \verb|aer|. ~\cite{Chen2018} use data from a major peer-to-peer lending marketplace in China to study whether female and male investors evaluate loan performance differently. You can add bib items (from Google Scholar, Mendeley, EndNote, and etc.) to \verb|reference.bib| file, and cite the bibkey in the \verb|tex| file.
-
-
-\nocite{EINAV2010,Havrylchyk2018} 
-
-\bibliographystyle{aer}
-\bibliography{reference}
-
-\addcontentsline{toc}{chapter}{参考文献}
-
-\end{document}

reference.bib

@@ -1,68 +1,71 @@
-@article{Zeng2017,
+
-abstract = {{\textcopyright} 2017 Zeng et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Peer-to-peer (P2P) lending, as a novel economic lending model, has triggered new challenges on making effective investment decisions. In a P2P lending platform, one lender can invest N loans and a loan may be accepted by M investors, thus forming a bipartite graph. Basing on the bipartite graph model, we built an iteration computation model to evaluate the unknown loans. To validate the proposed model, we perform extensive experiments on real-world data from the largest American P2P lending marketplace - Prosper. By comparing our experimental results with those obtained by Bayes and Logistic Regression, we show that our computation model can help borrowers select good loans and help lenders make good investment decisions. Experimental results also show that the Logistic classification model is a good complement to our iterative computation model, which motivates us to integrate the two classification models. The experimental results of the hybrid classification model demonstrate that the logistic classification model and our iteration computation model are complementary to each other. We conclude that the hybrid model (i.e., the integration of iterative computation model and Logistic classification model) is more efficient and stable than the individual model alone.},
+@article{en3,
-author = {Zeng, Xiangxiang and Liu, Li and Leung, Stephen and Du, Jiangze and Wang, Xun and Li, Tao},
+  title={{The Mechanism and Effectiveness of Credit Scoring of P2P Lending Platform: Evidence from Renrendai.com}},
-doi = {10.1371/journal.pone.0184242},
+  author={Li, Qiang and Chen, Liwen and Zeng, Yong},
-file = {:D$\backslash$:/Nuts/Reference/A decision support model for investment on P2P lending platform - Zeng et al. - 2017.pdf:pdf;:D$\backslash$:/Nuts/Reference/A decision support model for investment on P2P lending platform - Zeng et al. - 2017(2).pdf:pdf},
+  journal={China Finance Review International},
-isbn = {1111111111},
+  volume={8},
-issn = {19326203},
+  number={3},
-journal = {PLoS ONE},
+  pages={256--274},
-number = {9},
+  year={2018},
-pages = {1--18},
+  publisher={Emerald Publishing Limited}
-title = {{A decision support model for investment on P2P lending platform}},
-volume = {12},
-year = {2017}
-}
-@article{EINAV2010,
-author = {Einav, Liran And Cullen, Amy Finkelstein Mark R.},
-file = {:D$\backslash$:/Nuts/Reference/Estimating Welfare in Insurance Markets Using Variation in Prices - EINAV, CULLEN - 2010.pdf:pdf},
-isbn = {1932-6203 (Electronic) 1932-6203 (Linking)},
-issn = {19326203},
-journal = {Quarterly Journal of Economics},
-number = {August},
-pages = {877--921},
-pmid = {24710357},
-title = {{Estimating Welfare in Insurance Markets Using Variation in Prices}},
-volume = {CXXV},
-year = {2010}
-}
-@article{Veiga2018,
-abstract = {Would consumer surplus increase if annuity rates were age-neutral? This paper characterizes the socially optimal contractibility of a given signal in markets with adverse selection. A signal (e.g., age) partitions consumers into subsets (e.g., young and old). A regulator restricts price-discrimination on the basis of the signal if the consumer subsets where the level of cost is higher are also the subsets where there is greater deadweight loss due to adverse selection. Such signals are empirically common. To illustrate the welfare benefit of price discrimination policy, I use a structural model to estimate its impact on the UK annuities market. The model is estimated using proprietary data that include the annuity seller's estimate of each individual's longevity. I find that restricting price discrimination can increase consumer surplus by the equivalent of about {\pounds}6.5 million per year.},
-author = {Veiga, Andr{\'{e}}},
-file = {:D$\backslash$:/Nuts/Reference/The Impact of Price Discrimination in Markets with Adverse Selection - Veiga - 2018.pdf:pdf},
-keywords = {Adverse Selection,D41,L52,Price Discrimination,Structural Estimation JEL Classification Codes: D8},
-title = {{The Impact of Price Discrimination in Markets with Adverse Selection}},
-year = {2018}
 }
 
-@article{Chen2018,
+
-abstract = {We use data from a major peer-to-peer lending marketplace in China to study whether female and male investors evaluate loan performance differently. Controlling for variables of investor demographics, investor experience, and loan characteristics, we find that loans invested by female investors are more likely to default and have lower loan return in the future than loans invested by male investors. We define abnormal default or abnormal loan return as the part of the loan default or the part of loan return that is not explained by loan characteristics and find that the loans invested by female investors have higher abnormal default and lower abnormal loan return than the loans invested by male investors. Furthermore, female investors perform similarly to male investors in abnormal default or abnormal loan return when investors have high levels of education or income or when investors work in finance or information technology industries.},
+@article{en2,
-author = {Chen, Jia and Jiang, Jiajun and jane Liu, Yu},
+   author = {Carlstrom, Charles T and Fuerst, Timothy S},
-doi = {10.1016/j.jempfin.2018.06.004},
+   title = {{Agency Costs, Net Worth, and Business Fluctuations: A Computable General Equilibrium Analysis}},
-file = {:D$\backslash$:/Nuts/Reference/Financial literacy and gender difference in loan performance - Chen, Jiang, Liu - 2018.pdf:pdf},
+   journal = {The American Economic Review},
-issn = {09275398},
+   pages = {893-910},
-journal = {Journal of Empirical Finance},
+   ISSN = {0002-8282},
-keywords = {Financial Literacy, Gender Difference, Loan Default, Loan Return,Peer-to-peer Lending},
+   year = {1997},
-number = {71673007},
+   type = {Journal Article}
-pages = {307--320},
-title = {{Financial Literacy and Gender Difference in Loan Performance}},
-volume = {48},
-year = {2018}
 }
 
-@article{Havrylchyk2018,
+@article{en1,
-abstract = {The objective of our paper is to explore the role of P2P lending platforms through the prism of the theory of financial intermediation. P2P lending platforms perform the brokerage function of financial intermediaries by matching lenders' supply and borrowers' demand of funding, according to the risk and the maturity of their needs. Unlike banks, P2P lending platforms do not create money and do not perform risk and maturity transformation. However, they can organize secondary markets to trade loan contracts before maturity and some P2P lending platforms aim at providing a fixed income to lenders. To ensure efficient and sustainable financial intermediation, P2P lending platforms need to ensure that they are not subject to principal-agent problems and that their incentives coincide with those of lenders. The possibility of orderly resolution of P2P lending platforms failures might decrease moral hazard problems that are inherent in the modern financial intermediation.},
+   author = {Quadrini, Vincenzo},
-author = {Havrylchyk, Olena and Verdier, Marianne},
+   title = {{Financial Frictions in Macroeconomic Fluctuations}},
-doi = {10.1057/s41294-017-0045-1},
+   journal = {FRB Richmond Economic Quarterly},
-file = {:D$\backslash$:/Nuts/Reference/The Financial Intermediation Role of the P2P Lending Platforms - Havrylchyk, Verdier - 2018.pdf:pdf},
+   volume = {97},
-issn = {14783320},
+   number = {3},
-journal = {Comparative Economic Studies},
+   pages = {209-254},
-keywords = {Access to finance,Financial crisis,Information and communication technologies,Internet,Market structure,Online lenders,Peer-to-peer lending},
+   year = {2011},
-number = {1},
+   type = {Journal Article}
-pages = {115--130},
+}
-publisher = {Palgrave Macmillan UK},
+
-title = {{The Financial Intermediation Role of the P2P Lending Platforms}},
+@article{cn1,
-url = {https://doi.org/10.1057/s41294-017-0045-1},
+   author = {方军雄},
-volume = {60},
+   key = {fang1 jun1 xiong2},
-year = {2018}
+   title = {{所有制、制度环境与信贷资金配置}},
+   journal = {经济研究},
+   number = {12},
+   pages = {82-92},
+   ISSN = {0577-9154},
+   year = {2007},
+   type = {Journal Article}
+}
+
+@article{cn2,
+   author = {刘凤良 and 章潇萌 and 于泽},
+   key = {liu2 feng4 liang2 zhang1 xiao1 meng2 yu2 ze2},
+   title = {{高投资、结构失衡与价格指数二元分化}},
+   journal = {金融研究},
+   number = {02},
+   pages = {54-69},
+   ISSN = {1002-7246},
+   year = {2017},
+   type = {Journal Article}
+}
+
+@article{cn3,
+   author = {吕捷 and 王高望},
+   key = {lv3 jie2 wang2 gao1 wang4},
+   title = {{CPI 与 PPI “背离”的结构性解释}},
+   journal = {经济研究},
+   volume = {50},
+   number = {04},
+   pages = {136-149},
+   ISSN = {0577-9154},
+   year = {2015},
+   type = {Journal Article}
 }