sponsored by NASA Office of Space Science and held at the Goddard Space Flight Center, Greenbelt, Maryland, October 1977 ; editors, M. Neugebauer ... [and others]
sponsored by NASA Office of Space Science and held at the University of Chicago, January 19-21, 1978 ; editors, David Morrison, NASA, Office of Space Science, William C. Wells, Science Applications, inc. ; co-chairmen, Edward Anders, University of Chicago, David Morrison, NASA, Office of Space Science