@misc{fanger_hydra_hydrographic_1992, 
author={Fanger, H.-U.},
title={HYDRA: hydrographic measurement system},
year={1992},
howpublished = {conference lecture: Geesthacht (D);},
note = {Fanger, H.: HYDRA: hydrographic measurement system. French-German Workshop on Marine Monitoring/Sur-veillance Systems and Technologies. Geesthacht (D), 1992.}}