¹ Princeton University Observatory, Princeton, NJ 08544
² Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802
³ University of Washington, Department of Astronomy, Box 351580, Seattle, WA 98195
⁴ Max-Planck-Institut für extraterrestrische Physik, Postfach 1603, 85750 Garching, Germany
⁵ Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510
⁶ Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349-0059
⁷ Department of Physics and Astronomy, Johns Hopkins University, 3701 San Martin Drive, Baltimore, MD 21218
⁸ Department of Astronomy, California Institute of Technology, Pasadena, CA 91125
⁹ Department of Physics of Complex Systems, Eötvös University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary
¹⁰ Department of Astronomy and Research Center for the Early Universe, School of Science, University of Tokyo, Hongo, Bunkyo, Tokyo 113-0033, Japan
¹¹ Astronomy & Astrophysics Center, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637
¹² Institute for Cosmic Ray Research, University of Tokyo, Midori, Tanashi, Tokyo 188-8502, Japan
¹³ Institute for Advanced Study, Olden Lane, Princeton, NJ 08540
¹⁴ U.S. Naval Observatory, 3450 Massachusetts Avenue NW, Washington, DC 20392-5420
¹⁵ Department of Physics, University of Michigan, 500 East University, Ann Arbor, MI 48109
¹⁶ US Naval Observatory, Flagstaff Station, P.O. Box 1149, Flagstaff, AZ 86002-1149