%&LaTeX
\documentclass{article}

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

\begin{document}

\begin{thebibliography}{1}

\bibitem{Bischoff_etal1986} Bischoff, W. D., Dettmer, R., \& W{\"a}chtler, K. (1986). \textit{Die Flu{\ss}perlmuschel} (Vol. 64).

\end{thebibliography}

\end{document}

