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\bibitem{Nickels_etal2002} Nickels, C., von der Ahe, B., Beck, V., Trace, M., B{\"o}llinger, L., Paoli, L., et al. (2002). \textit{Cannabispolitik im europ{\"a}ischen Vergleich : Dokumentation des Kongresses}  (C. Nickels, Ed.). Berlin: B{\"u}ndnis 90/Die Gr{\"u}nen, Bundesfraktion.

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