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\bibitem{Schirtz_etal2005} Schirtz, A., H{\"a}mmig, R., Broers, B., B{\"o}sch, L., \& Stohler, R. (2005). Suchtforschung des BAG. In Bundesamt f{\"u}r Gesundheit (Ed.), (pp. 46--51). Berne: Bundesamt f{\"u}r Gesundheit (BAG).

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