\documentclass[twoside,12pt,leqno]{article}
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%%%%% Martin Schlichenmaier 24.2.2006
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\widowpenalty=10000
\clubpenalty=10000
\raggedbottom\oddsidemargin .4in
\evensidemargin .4in
\marginparwidth =1in
\textwidth 14.6cm
\topmargin 15mm\textheight 620pt
\advance\topmargin by -\headheight\advance\topmargin by -\headsep
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%%\setcounter{page}{33}
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\newcommand{\tmvolxx}{xx}
\newcommand{\tmyearyyyy}{yyyy}
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\newcommand{\FirstPageHead}[3]{
{\footnotesize
\vskip -8mm
\centerline {Travaux math\'ematiques, \quad
Volume #1 (#2),
#3,\quad \copyright\ Universit\'e du Luxembourg}}\vspace{-3mm}}
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%%%%% The following are macro-packages which might be used
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%%%%%%%%%%% DO NOT CHANGE
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\usepackage{amsmath}
\usepackage{amsthm}
\usepackage{amssymb}
\usepackage{amscd}
\usepackage{graphicx}
\usepackage{epsfig}
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%%The following organizes the numbering of theorem-like
%%enviroments etc.
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% Makes the equation numbering subordinate to the section numbers.
\numberwithin{equation}{section}
% Theorems, Lemmas and the like, should be typeset in italic
\newtheorem{theorem}{Theorem}[section]
\newtheorem{lemma}[theorem]{Lemma}
\newtheorem{proposition}[theorem]{Proposition}
\newtheorem{corollary}[theorem]{Corollary}
\newtheorem{claim}[theorem]{Claim}
\newtheorem{conjecture}[theorem]{Conjecture}
% Examples, Remarks, Definitions etc. typeset with upshape
\theoremstyle{definition}
\newtheorem{definition}[theorem]{Definition}
\newtheorem{example}[theorem] {Example}
\newtheorem{problem}[theorem]{Problem}
\newtheorem{remark}[theorem]{Remark}
\newtheorem*{remarku}{Remark}
\newtheorem*{exampleu}{Example} % The '*' makes it unnumbered
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%%%%% If you prefer to numerate each type separately
%%%%% Comment out the preceedings group of commands and
%%%%% Uncomment the following group
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% Makes the equation numbering subordinate to the section numbers.
\numberwithin{equation}{section}
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%% % Theorems, Lemmas and the like, should be typeset in italic
%% \newtheorem{theorem}{Theorem}[section]
%% \newtheorem{lemma}{Lemma}[section]
%% \newtheorem{proposition}{Proposition}[section]
%% \newtheorem{corollary}{Corollary}[section]
%% \newtheorem{claim}{Claim}[section]
%% \newtheorem{conjecture}{Conjecture}[section]
%% % Examples, Remarks, Definitions etc. typeset with upshape
%% \theoremstyle{definition}
%% \newtheorem{definition}{Definition}[section]
%% \newtheorem{example}{Example} [section]
%% \newtheorem{problem}{Problem}[section]
%% \newtheorem{remark}{Remark}[section]
%% \newtheorem*{remarku}{Remark}
%% \newtheorem*{exampleu}{Example} % The '*' makes it unnumbered
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\allowdisplaybreaks
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\begin{document}
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% Leave the following commands
\thispagestyle{empty}
% The following line will be adapted for the final
% print version
\FirstPageHead{\tmvolxx}{\tmyearyyyy}{\pageref{firstpage}--\pageref{lastpage}}
\label{firstpage}
% Parameters: Volume, year, page range,
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%%%%%%%% START OF THE CONTRIBUTION
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%%%% please give some keywords:
%%%%
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%%%% Please give one or more AMS classification numbers
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%%%% private macros
%%%% do not use renewcommand (i.e. do not redefine
%%%%% standard Latex-Commands
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%%%%% end of private macros
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%%% Here the top-matter of your Article starts
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%%%% Please replace by your data
%%% This are the running heads (please adapt)
\markboth{your name}{your (short) title}
$ $
\bigskip
\bigskip
%%%% Title
\centerline{{\Large Your title}}
%%% Author
\bigskip
\bigskip
\centerline{{\large by XXXX (your name)}}
\vspace*{.7cm}
\begin{abstract}
This is your abstract
\end{abstract}
%%%% Leave the following commands
\pagestyle{myheadings}
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\section{Introduction}
This is your introduction.
\section{This is the next section}
\begin{theorem}\label{null}
This is the statement of the theorem.
\end{theorem}
\begin{proof}
This is the proof of the theorem.
\end{proof}
The above Theorem \ref{null} is very useful.
It can be found in
\cite{GH}.
\section{This is the next section, etc.}
\begin{theorem}\label{one}
This is the statement of the theorem.
\end{theorem}
The following is a proposition
\begin{proposition}
$-1=\exp{\pi i}$.
\end{proposition}
\begin{remarku}
This is an unnumbered remark.
\end{remarku}
\begin{remark}
This is an numbered remark.
\end{remark}
The following is a numbered equation
\begin{equation}
-1=\exp{\pi i}.
\end{equation}
The following is a unnumbered equation
\begin{equation*}
-1=\exp{\pi i}.
\end{equation*}
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%%%%% The bibliography
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\begin{thebibliography}{11}
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\bibitem{GH}
Ph. Griffiths and J.~Harris, \emph{Principles of algebraic geometry}, John
Wiley, New York, 1978.
\end{thebibliography}
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%% The address
\noindent
your name \\
your address 1\\
your address 2\\
etc.\\
your email
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%%%%%%%%%%%%% Leave the following command
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\label{lastpage}
\end{document}