I would like to create a document with multiple abstracts for a conference. Below, there is code that produces only a single abstract. How can I produce several abstracts using this code?
\documentclass[twoside]{article}
\usepackage{amssymb,amsfonts,amssymb,amsthm}
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%%%%%%%PAGE FORMAT - PLEASE DO NOT MODIFY!!!!
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\pagestyle{myheadings} \topmargin =-20pt \marginparwidth = 45pt
\evensidemargin = -15pt \oddsidemargin = -15pt \textheight = 670pt
\textwidth = 500pt \linespread{1.2}
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\renewcommand{\theequation}{\arabic{section}.\arabic{equation}}
\newtheorem{myth}{Teorema}[section]
\newtheorem{mylem}{Lema}[section]
\newtheorem{mypro}{Proposi\c c\~ao}[section]
\newtheorem{mydef}{Defini\c c\~ao}[section]
\newtheorem{myrem}{Observa\c c\~ao}[section]
\newtheorem{mycor}{Corol\'ario}[section]
\newtheorem{myex}{Exemplo}[section]
\newcommand{\cqd}{\hspace{10pt}\fbox{}}
\newcommand{\cqdf}{\hspace{10pt}\rule{5pt}{5pt}}
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\begin{document}
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%%%%% PAGE HEADER - PLEASE DO NOT MODIFY!!!
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\pagestyle{empty} %%
\title{
\vspace{-1in}\parbox{\linewidth}{\footnotesize\noindent {\sc\bf
Conference}
\newline
{\sc \bf Universidade}
\newline
\bf Cidade - data}
\newline\newline
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%%%%%%%%%%%%%%%%%%% END OF THE HEADER %%%%%%%%%%%%%%%%%%%%%%%%
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%%% WRITE THE TITLE IN THE FOLLOWING COMMAND WITH
%%% lower case (minuscule) letters!
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{\sc Title}
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\author{\sc
Autor \thanks{Departament, University,\, email: } }}
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%% DO NOT FILL THE COMMAND \date{} BELOW, LET IT EMPTY!!
%% PLEASE, KEEP IN THE TEXT THE COMMANDS \maketitle AND \thispagestyle{empty}
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\date{}
\maketitle \thispagestyle{empty} \vspace{-10pt}
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Abstract
\scand\bfhave not been defined by default in latex since 1993, althougharticleclass defines the mfor compatibility with documents from before that, but if you do use them they do not combine\sc\bfis the same as\bfit does not denote bold small caps. It is hard to answer your question as the commands you show are not suitable for an abstract collection, you do not want\authorand\maketitlefor a collection of abstracts by different authors, just set each absract as (say) a new\section