@misc{wilken_the_north_1994, 
author={Wilken, R.-D.},
title={The North Sea pollution: an example of problems with an international shallow water area},
year={1994},
howpublished = {conference lecture: Bombay (IND); 15.12.1994},
note = {Online available at: \url{} (DOI). Wilken, R.: The North Sea pollution: an example of problems with an international shallow water area. Vortrag im B.A.R.C.. Bombay (IND), 1994.}}