@misc{wilken_approaches_to_1991, 
author={Wilken, R.-D.},
title={Approaches to measure mercury and mercury species in air},
year={1991},
howpublished = {conference lecture: Geesthacht (D); 23.-24. September 1991},
note = {Online available at: \url{} (DOI). Wilken, R.: Approaches to measure mercury and mercury species in air. 3rd International Workshop on Modelling the Atmospheric Transport and Deposition of Mercury. Geesthacht (D), 1991.}}