Affiliation: | 1.Bundesanstalt für Geowissenschaften und Rohstoffe (BGR), Stilleweg 2, 30655, Hannover, Deutschland ;2.Global Institute for Water Security, School of Environment and Sustainability, University of Saskatchewan, Saskatoon, Kanada ;3.University of Namibia (UNAM), 340 Mandume Ndemufayo Avenue, Windhoek, Namibia ; |