1. Main Astronomical Observatory, Academy of Sciences of the Ukraine, Golosiiv Woods, UA-03680 Kyiv-127, Ukraine
2. Centre for Astrophysics Research, University of Hertfordshire, College Lane, Hatfield AL10 9AB, UK
3. Astrophysics Group, Lennard Jones Laboratory, Keele University, Keele, Staffordshire ST5 5BG, UK
4. Physical Research Laboratory, Navrangpura, Ahmedabad, Gujarat 380009, India
5. Gemini Observatory, 670 N. Aohoku Place, Hilo, HI 96720, USA
6. INAF Astronomical Observatory of Padova, I-36012 Asiago (VI), Italy
7. School of Physics & Astronomy, Minnesota Institute for Astrophysics, University of Minnesota, 116 Church Street SE, Minneapolis, MN 55455, USA
8. School of Earth and Space Exploration, Arizona State University, Box 871404, Tempe, AZ 85287-1404, USA