1. Department of Earth Sciences; University of Geneva; Geneva Switzerland
2. Department of Terrestrial Magnetism; Carnegie Institution for Science; Washington DC USA
3. Department of Earth Sciences; Institute of Geochemistry and Petrology, ETH Zürich; Zurich Switzerland
4. Department of Water Resources and Drinking Water; EAWAG; Dübendorf Switzerland
5. Chemostrat Ltd.; Welshpool UK
6. School of Earth and Environmental Sciences; University of Portsmouth; Portsmouth UK