¹ Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721, USA
² Research Center for Space & Cosmic Evolution, Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577, Japan
³ Max Planck-Institut für Extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching, Germany
⁴ Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA
⁵ Max Planck Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg, Germany
⁶ Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
⁷ California Institute of Technology, MC 105-24, 1200 East California Boulevard, Pasadena, CA 91125, USA
⁸ Institute for Astronomy, 2680 Woodlawn Dr., University of Hawaii, Honolulu, HI 96822, USA
⁹ Dipartimento di Fisica, Università di Roma La Sapienza, P.le A. Moro 2, 00185 Roma, Italy
¹⁰ Observatories of the Carnegie Institute of Washington, Santa Barbara Street, Pasadena, CA 91101, USA
¹¹ European Southern Observatory, Karl-Schwarschild-Strasse 2, D-85748 Garching, Germany
¹² Hubble Fellow