Organizations
- American Association of Variable Star Observers (AAVSO)
- 25 Birch St.
- Cambridge, MA 02138
- Astronomical Society of the Pacific
- 390 Ashton Ave.
- San Francisco, CA 94112
- British Astronomical Association
- Burlington House, Piccadilly,
- London W1V 9AG
- Royal Astronomical Society of Canada
- 136 Dupont St.
- Toronto Ontario M5R 1V2