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\bibitem{Muellhaupt2009} M{\"u}llhaupt, B. (2009). HBV/HCV coinfection. In \textit{1st International Symposium on Hepatitis care in substance users} (22). Zurich: Universit{\"a}tsspital Z{\"u}rich, Klinik f{\"u}r Gastroenterologie und Hepatologie.

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