1. Astronomical Institute of the Slovak Academy of Sciences, SK-05960 Tatranská Lomnica
2. Main Astronomical Observatory of the National Academy of Sciences of Ukraine, 27 Zabolotnoho Str., 03143 Kyiv, Ukraine
3. Taras Shevchenko National University of Kyiv, 3 Observatorna Str., 04053 Kyiv, Ukraine
4. Space Sciences Laboratory, University of California Berkeley, 7 Gauss Way Berkley, CA 94720, USA
5. George Mason University, 4400 University Dr, Fairfax, VA 22030, USA
6. NASA/GSFC, 8800 Greenbelt Rd, Greenbelt, MD 20771, USA
7. Special Astrophysical Observatory of the Russian Academy of Sciences, 369167 Nizhnij Arkhyz, Russia