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\bibitem{Berg_etal1989} Berg, R., Blank, S., \& Strubelt, T. (1989). \textit{Fische in Baden-W{\"u}rttemberg}. Stuttgart: Ministerium f{\"u}r L{\"a}ndlichen Raum, Ern{\"a}hrung, Landwirtschaft und Forsten Baden-W{\"u}rttemberg.

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