%&LaTeX
\documentclass{article}

\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{textcomp}

\begin{document}

\begin{thebibliography}{5}

\bibitem{Kaurova_etal2004} Kaurova, N. S., Finkel, M. I., Maslennikov, S. N., Vahtomin, Y. B., Antipov, S. V., Smirnov, K. V., et al. (2004). Submillimeter mixer based on YBa$_{2}$Cu$_{3}$O$_{7-x}$ thin film. In \textit{Proc. 1-st conf. Fundamental problems of high temperature superconductivity} (291). Moscow-Zvenigorod.

\end{thebibliography}

\end{document}

