@misc{markert_oekologisches_freilandpraktikum_1992, 
author={Markert, B.},
title={Oekologisches Freilandpraktikum},
year={1992},
howpublished = {lecture: Universitaet Osnabrueck; WS 1991-1992},
note = {Online available at: \url{} (DOI). Markert, B.: Oekologisches Freilandpraktikum. Universitaet Osnabrueck, 1992.}}