@misc{spengler_a_cheap_1996, 
author={Spengler, M., dos Santos, R. L. C., Hempel, M.},
title={A cheap and simple mercury filter for Brazilian gold mining areas},
year={1996},
howpublished = {conference lecture: Hamburg (D);},
note = {Spengler, M.; dos Santos, R.; Hempel, M.: A cheap and simple mercury filter for Brazilian gold mining areas. 4th International Conference: Mercury as a Global Pollutant. Hamburg (D), 1996.}}