1. NRC ‘Kurchatov Institute’ – Institute for Theoretical and Experimental Physics, B. Cheremushkinskaya St. 25, 117218 Moscow, Russia
2. Institute of Astronomy, Russian Academy of Sciences, Pyatnitskaya St. 48, 119017 Moscow, Russia
3. Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching, Germany
4. Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721-0065, USA
5. Department of Physics, University of California, Santa Barbara, CA 93106-9530, USA
6. Las Cumbres Observatory, 6740 Cortona Dr, Suite 102, Goleta, CA 93117-5575, USA
7. Department of Physics and Astronomy, University of California, 1 Shields Avenue, Davis, CA 95616-5270, USA