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\usepackage{fancyhdr}
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\lhead{\footnotesize{{\large{National Conference on Applied Mathematics and Didactics NCAMD2021, Constantine-Algeria.
19 Juin, 2021.} }}}


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%%%%%%%%%%%%%%% PAPER %%%%%%%%%%%%%%%%%%%%
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\begin{document}


%=====================================================================================================================
%Title
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\vspace{2mm} \hrule
%---------------------------------
%%%%%%%%%%%%%%%%%%%%%%Author1
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\\Email: }

\adresse{Address of Author2
\\Email: }

\adresse{Address of Author3
\\Email: }
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 \begin{abstract}

...............................................................
\end{abstract}
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 \vspace{0.5cm}
 %--------------------------------------------------------------------------------------
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\bibitem{2}
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\end{document}
