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\bibitem{Winkler1995} Winkler, C. (1995). \textit{Untersuchungen zur Biologie und {\"O}kologie des Str{\"o}mers (Leuciscus souffia agassizi Val.) in n{\"o}rdlichen Bodenseezufl{\"u}ssen}. Ulm: Universit{\"a}t Ulm.

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