\begin{document}
\section*{Introduction}\label{s0}Problems of a ...
\section{Theoretical part} \label{s2}Consider the ...
\section{Experimental part}\label{s3}
The electric field of an ...
\section*{Conclusion}\label{s4}Thus, the ..
\begin{thebibliography}{587}\label{sb}
\bibitem{Ym1}
\by N.\,S.~Umov,
\book Trudyi,
\publaddr Moscow,
\publ Nauka,
\yr 1917
(in Jewish).
\end{thebibliography}
\end{document}