1. MIT Haystack Observatory, Off Route 40, Westford, MA 01886, USA.
2. Harvard Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA.
3. Steward Observatory, Arizona Radio Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721–0065, USA.
4. Department of Astronomy, University of California Berkeley, Hearst Field Annex, Berkeley, CA 94720, USA.
5. Perimeter Institute, 31 Caroline Street, North Waterloo, Ontario N2L 2Y5, Canada.
6. Department of Physics and Astronomy, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2l 3G1, Canada.
7. Caltech Submillimeter Observatory, 111 Nowelo Street, Hilo, HI 96720, USA.
8. James Clerk Maxwell Telescope, Joint Astronomy Centre, 660 North A'ohoku Place University Park, Hilo, HI 96720, USA.
9. Academia Sinica Institute for Astronomy and Astrophysics, 11F Astronomy-Mathematics Building, National Taiwan University, No. 1, Roosevelt Road, Section 4 Taipei 10617, Taiwan, R.O.C.
10. National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan.
11. The Graduate University for Advanced Studies, Osawa, Mitaka, Tokyo 181-8588, Japan.
12. Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany.
13. Owens Valley Radio Observatory, California Institute of Technology, 100 Leighton Lane, Big Pine, CA 93513–0968, USA.
14. Netherlands Organisation for Scientific Research, Laan van Nieuw Oost-Indie 300, NL2509 AC The Hague, Netherlands.