@misc{wilken_analysis_of_1990, 
author={Wilken, R.-D., Hintelmann, H.},
title={Analysis of mercury-species in sediments},
year={1990},
howpublished = {GKSS report},
note = {Wilken, R.; Hintelmann, H.: Analysis of mercury-species in sediments. In: Broekaert, J.; Guecer, S.; Adams, F. (Ed.): Metal speciation in the environment - NATO ASI Series. Berlin: Springer. 1990. 339-359.}}