Affiliation: | Uppsala Astronomical Observatory, Box 515, S-751 20 Uppsala, Sweden; Department of Astronomy, University of Western Ontario, London, Ontario N6A 3K7, Canada; Institute of Astronomy, Russian Academy of Sciences, Pyatnitskaya 48, 109017 Moscow, Russia; Institute for Astronomy, University of Vienna, Türkenschanzstraße 17, 1180 Vienna, Austria |