@misc{klapper_ecotechnologies_for_1989, 
author={Klapper, H.},
title={Ecotechnologies for improving water quality},
year={1989},
howpublished = {conference lecture: Prague (CZ);},
note = {Klapper, H.: Ecotechnologies for improving water quality. World Fed. of Engineering Organizations: Technical Congress '89. Prague (CZ), 1989.}}