@misc{paul_membranes__2002, 
author={Paul, D.},
title={Membranes},
year={2002},
howpublished = {lecture: Universitaet Potsdam; 18.07.2002},
note = {Online available at: \url{} (DOI). Paul, D.: Membranes. Universitaet Potsdam, 2002.}}