@misc{wilken_mercury_problems_1992, 
author={Wilken, R.-D.},
title={Mercury problems and the global mercury cycle},
year={1992},
howpublished = {conference lecture: Magdeburg (D); 18. Juni 1992},
note = {Online available at: \url{} (DOI). Wilken, R.: Mercury problems and the global mercury cycle. UNESCO-Kurs. Magdeburg (D), 1992.}}