%&LaTeX
\documentclass{article}

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

\begin{document}

\begin{thebibliography}{5}

\bibitem{Tong_etal2003} Tong C-YE, Meledin D, Blundell R, Erickson N, Kawamura J, Mehdi I, et al. A 1.5 THz hot-electron bolometer mixer operated by a planar diode-based local oscillator [abstract]. In: Proc. 14$^{th}$ Int. Symp. Space Terahertz Technol.; 2003. 286.

\end{thebibliography}

\end{document}

