%&LaTeX
\documentclass{article}

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

\begin{document}

\begin{thebibliography}{1}

\bibitem{Rehm-Berbenni_etal2005} Rehm-Berbenni, C., Druta A., {\r A}berg, G., Neguer J., K{\"u}lls, C., Patrizi, G., et al. (2005). \textit{Isotope Technologies Applied to the Analysis  of Ancient Roman Mortars}.

\end{thebibliography}

\end{document}

