Paired and interacting galaxies : proceedings of a conference sponsored by the International Astronomical Union, the University of Alabama at Tuscaloosa, and the National Aeronautics and Space Administration and held at the University of Alabama at Tuscaloosa, Alabama, December 4-7, 1989 / International Astronomical Union Colloquium, no. 124 ; edited by J.W. Sulentic and W.C. Keel, C.M. Telesco.