1. South African Astronomical Observatory, PO Box 9, 7935, Observatory, South Africa
2. Astronomy Department, University of Cape Town, 7701, Rondebosch, South Africa
3. The Observatories, Madingley Rd, Cambridge CB3 0HA, England
4. Formerly, Lick Observatory and Institute of Astronomy, University of Hawaii, Honolulu, HI 96822, USA