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\title{\textbf{\LARGE Άρθρο}\vspace{10mm}}
\author{
{ΑΘανάσιος Παρασκευόπουλος}
\\{Μεταπτυχιακός φοιτητής Μαθηματικών στο Ε.Α.Π}
\\{{\latintext{at.paraskevopoulos@protonmail.ch}}}}
\date{}
\begin{document}
\gr
\maketitle
\begin{abstract}
\end{abstract}
\selectlanguage{english}
\begin{center}
\title{\textbf{\LARGE{Article}\vspace{10mm}}}
\\
\author{
{Athanasios Paraskevopoulos}
\\{MSc.candidate in Mathematics at Hellenic Open University}}
\end{center}
\begin{abstract}
\end{abstract}
\newpage
\gr
\section{}
\newpage
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