1. Institute of Geophysics and Meteorology University of Cologne Cologne Germany
2. The Johns Hopkins University Applied Physics Laboratory Laurel MD USA
3. Southwest Research Institute San Antonio TX USA
4. University of Texas at San Antonio San Antonio TX USA
5. Department of Physics and Astronomy University of Iowa Iowa City IA USA
6. NASA Goddard Space Flight Center Greenbelt MD USA
7. Space Research Corporation Annapolis MD USA
8. Laboratory for Atmospheric and Space Physics University of Colorado Boulder CO USA
9. School of Physics and Astronomy Minnesota Institute for Astrophysics University of Minnesota Minneapolis MN USA