%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% The abstract must be written in LaTeX2e               %%
%% Make sure that your abstract can be compiled before   %%
%% you send it to the organizer.                         %%
%% Do not use personal macros in your TeX file, and,     %%
%% for the sake of making your abstract understandable   %%
%% to a large audience and to avoid difficulties with    %%
%% the handling of your file, please limit the use of    %%
%% formulas as much as possible.                         %%
%% We suggest that you do not include references in      %%
%% your abstract. In case that you must have references, %%
%% then do not use \cite commands.                       %%
%%                                                       %%
%% For labels, try to write : \label{yourname01},        %%
%% \label{yourname02}...                                 %%
%% Your abstract should be no more than one page long.   %%
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\documentclass{article}
\usepackage{amsthm,amsmath,amssymb,latexsym}
\pagestyle{empty}
\textwidth=12.8cm
\textheight=21.7cm
\hoffset=-0.3in
\voffset=-0.6in
\parskip=6pt
\lineskip=18pt
%------------------------------------------------------------
\begin{document}
\baselineskip=15pt

\centerline{\large \bf Title of the Abstract}

\centerline{\large \bf Title to be Continued Here if Too Long}

\bigskip

\centerline{Author 1}
\centerline{\it Institution Name,Country}
\centerline{e-mail {\tt Author 1}}

%%% in case of several authors:
\smallskip
\centerline{Author 2}
\centerline{\it Institution Name,Country}
\centerline{e-mail {\tt Author 2}}
%%%

\bigskip
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\par
%   Text of the abstract

\bigskip

%%% in case of several authors:
{\bf  Presented by ...}
%%%

\end{document}