\documentclass[12pt,]{article}
\usepackage[cp1251]{inputenc}
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\usepackage[russian]{babel}

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\begin{document}

UDK 511.335

\begin{center}
{\Large \bf Title of the talk}

\medskip
{\large F.~S. Surname (City)}

e-mail address
\end{center}

Abstracts is limited to 3 pages.

Please don't use your own commands.

\begin{Theorem}  

Use the standard command for theorems, lemmas, corollaries and so on.
\end{Theorem}

List of references should contain only those papers (enumerated in order of citation), which are referenced in the text


\renewcommand{\refname}{References}
\begin{thebibliography}{99}

\bibitem{Sample1} Surname F.\,S., Title of paper // Title of journal. 1989. Vol. 67, no. 1 (23). P. 21--24.

\bibitem{Sample2} Surname F.\,S., Title of book. -- City: Publisher, 1989. 506~p.

\end{thebibliography}
\medskip
\noindent Affiliation. E.g., Ohio State University

\noindent Received **.**.2015
\end{document}
