1. National Bureau of Standards and the University of Colorado, Boulder
2. University of Maryland
3. Princeton University
4. Air Force Cambridge Research Laboratories
5. Wesleyan University, is at the National Bureau of Standards
6. University of California, Los Angeles
7. University of Texas, Austin
8. NASA Goddard Space Flight Center
9. McDonald Observatory of the University of Texas
10. Jet Propulsion Laboratory of the California Institute of Technology