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\bibitem{Gothuey_etal2007} Gothuey, I., Fink, A., H{\"a}mmig, R., \& f{\"u}r Suchtmedizin, S. G. (2007). \textit{Drogenabh{\"a}ngigkeit : gel{\"a}ufige psychiatrische Probleme}  (various, Ed.). Basel: Karger.

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