1. IUCAA, Post Bag 4, Ganeshkhind, Pune 411 007, India
2. Institute of Physics and Research Centre of Theoretical Physics and Astrophysics, Silesian University in Opava, Bezručovo nám.13, CZ-74601 Opava, Czech Republic
3. National University of Uzbekistan, Tashkent 100174, Uzbekistan
4. Ulugh Begh Astronomical Institute, Astronomicheskaya 33, Tashkent 100052, Uzbekistan