1. Office of Space Research and Technology; Academy of Athens; Athens Greece
2. Max-Planck-Institut für Sonnensystemforschung; Göttingen Germany
3. Deptartement of Climate, Space sciences & Engineering; University of Michigan; Ann Arbor MI USA
4. Applied Physics Laboratory; Johns Hopkins University; Baltimore MD USA
5. Harford Research Institute; MD USA
6. Department of Physics; University of Maryland; College Park MD USA