| Affiliation: | Department of Physics, Bristol University, H. H. Wills Laboratory, Tyndall Avenue, Bristol BS8 1TL; Institut d'Astrophysique de Paris, 98bis, Boulevard Arago, F75014 Paris, France; Sterrewacht Leiden, PO Box 9513, NL 2300RA Leiden, the Netherlands; Astrophysics, Cavendish Laboratory, Madingley Road, Cambridge CB3 0HE; Department of Astronomy, 601 Campbell Hall, University of California, Berkeley, CA 94110, USA; Max-Planck-Institut für extraterrestrische Physik, PO Box 1603, 85740 Garching, Germany |
