\section{Bibliography} \subsection{Sources} \begin{itemize} \item Versuchsanleitung Positronenvernichtung, Andres van der Schaaf, 15.02.06 \end{itemize} \subsection{Graphics} \begin{itemize} \item Figure \ref{Na-decay}: \url{https://www.nucleonica.com/Application/ReducedDecaySchemes/Na22_RDS.png} \end{itemize}