Annu. Rev. Astron. Astrophys. 1989. 27:
235-277 Copyright © 1989 by Annual Reviews. All rights reserved |
For a Pdf version of the article, click
here.
For a Postscript version of the article, click
here.
Table of Contents
1 Visiting Astronomer, Canada-France-Hawaii Telescope, operated by the National Research Council of Canada, the Centre National de la Recherche Scientifique of France, and the University of Hawaii.
2 Alfred P. Sloan Fellow.