1. Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
2. Institut für Geophysik und Extraterrestrische Physik; Technische Universität Braunschweig; Braunschweig Germany
3. British Antarctic Survey; Natural Environment Research Council; Cambridge UK
4. Department of Physics and Astronomy; University of Iowa; Iowa City Iowa USA
5. Department of Space Physics; Institute of Atmospheric Physics; Prague Czech Republic
6. Faculty of Mathematics and Physics; Charles University; Prague Czech Republic
7. Institute of Geophysics and Planetary Physics; University of California; Los Angeles California USA
8. CSPAR; University of Alabama in Huntsville; Huntsville Alabama USA