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\usepackage{amsthm,amssymb,amstext}
\usepackage{amsfonts}
\usepackage{float}
\usepackage{amsmath}
\usepackage{latexsym}
\usepackage{amsopn}
\newtheorem{theorem}{Theorem}
\newtheorem{definition}{Definition}
\textwidth13cm
\headsep 15pt
\textheight19cm
\oddsidemargin 63pt
\evensidemargin 63pt
\parindent0pt
\newcommand\Title[1]{\smallskip{\begin{center}{\Large \bf #1}\end{center}}}
\newcommand\Author[2]{\rm\it\large #1\footnote{#2}}
\pagestyle{empty}
\begin{document}
%%%%%%%%%%%%%%%%%%%%%%%%%% LOGO %%%%%%%%%%%%%%%%%%
\begin{tabular}{l} {\small XV-th
International } \\
{\small Conference on Mathematics } \\
{\small Informatics and Related Fields}
\end{tabular}
%%%%%%%%%%%%%%%%%%%%%%% TITLE %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\Title{Title of talk should not exceed two lines of text}
%%%%%%%%%%%%%%%%%%% AUTHOR(S) %%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{center}
\Author{Jan Nowak}{Rzeszow University of Technology, Rzeszow, Poland,
e-mail: jnowak@...} \Author{Jan Kowalski}{Rzeszow University of Technology, Rzeszow, Poland,
e-mail: jkowalski@...}
\end{center}
%%%%%%%%%%%%%%%%%% TEXT OF ABSTRACT %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Text of abstract should be clear, brief and announce a main idea of the lecture. Full abstract (with a heading and footnotes) does not exceed one page (13 cm x 19 cm) and should be arranged as follows:
\begin{itemize}
\item 3 cm - logo of the conference - made by organizers,
\item 1,5 cm - title of talk - use instruction -- \texttt{$\backslash$Title},
\item 1,5 cm -- author(s) of the work -- use reference \texttt{$\backslash$Author\{tekst1\}\{tekst2\}}, where \texttt{
tekst1} -- name of author(s), \texttt{tekst2} -- affiliation, address and e-mail of author(s).
\end{itemize}
Main text of the abstract should be written in
\texttt{$\backslash$rm 11pt} Times New Roman font, and should not exceed the area of 13 cm x 13cm.
{\bf In order to obtain right format of abstract we suggest to use such a sample file.}
Only Definitions and Theorems are permitted, numbered separately, in the style as follows:
\begin{definition} Let A be an open set ...\end{definition}
\begin{theorem} Let A be an open set ...
\end{theorem}
References (if any) should be listed in the following style:
\medskip {\small \noindent [1] J. Nowak, {\it Starlike and convex function}, Proc. Amer. Math. Soc. {\bf 1}(2008), 1-11.}
\end{document}