1. Sternberg Astronomical Institute; Moscow M.V. Lomonosov State University; 13 Universitetski prospekt; Moscow; 119991; Russia
2. Institute of Astronomy of the Russian Academy of Sciences; 48 Pyatnitskaya Street; Moscow; 119017; Russia
3. National Astronomical Observatories/Xinjiang Observatory; The Chinese Academy of Sciences; Urumqi; 830011; China