%&LaTeX
\documentclass{article}

\usepackage[latin1]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{textcomp}

\begin{document}

\begin{thebibliography}{10}

\bibitem{Haempel1911} Haempel, O. (1911). \textit{Zur Frage des H{\"o}rverm{\"o}gens der Fische} (Vol. IV).

\end{thebibliography}

\end{document}

