1. University of British Columbia, Department of Physics and Astronomy, Vancouver, British Columbia, Canada
2. University of California—Berkeley, Astronomy Department, Berkeley, California, United States
3. Max Planck Institute for Radio Astronomy, Bonn, Germany
4. University of California—Los Angeles, Division of Astronomy and Astrophysics, Los Angeles, California, United States
5. The Aerospace Corporation, El Segundo, California, United States
6. W. M. Keck Observatory, Kamuela, Hawaii, United States