1989 Comet Handbook
1989 DA
1989 DA.
1989 December 8 meeting of the Royal Astronomical Society
1989 FB.
1989 FC.
1989 February 10 meeting of the Royal Astronomical Society
1989 IEEE Nuclear Science Symposium, San Francisco, CA, Jan. 17-19, 1990, Proceedings
1989 ISSOL Meeting, Prague (Czechoslovakia), 3 - 8 Jul 1989.
1989 JA
1989 JA.
1989 January 13 meeting of the Royal Astronomical Society
1989 Light Curves of BH Vir
1989 May 12 meeting of the Royal Astronomical Society
1989 N 1.
1989 NA
1989 November 10 meeting of the Royal Astronomical Society
1989 OB
1989 October 13 meeting of the Royal Astronomical Society
1989 P/Brorsen-Metcalf, la cometa dell'estate.