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\bibitem{Bohl_etal1989} Bohl, E., Strohmeier, W., Leuner, E., Negele, R. D., Pscheidl, M., \& Heise, J. (1989). \textit{Untersuchungen an Flu{\ss}krebsbest{\"a}nden}. Wielenbach: Bayerische Landesanstalt f{\"u}r Wasserforschung.

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