%0 book part %@ %A Fanger, H.-U.,Kappenberg, J.,Kuhn, H.,Maixner, U.,Milferstaedt, D. %D 1990 %J Estuarine water quality management: monitoring, modelling and research - Coastal and estuarine studies %N %P 211-216 %T The hydrographic measuring system HYDRA %U %X