NGC 6664
Number of stars per data source
Reference 221 : 2 stars
Reference 532 : 9 stars
References
- 221
- Sowell J.R
- (1987) Astrophys. J. Suppl. 64, 241
- Yellow evolved stars in open clusters
- 1987ApJS...64..241S
- 532
- Walker M.F., Bidelman W.P.
- (1960) Publ. Astr. Soc. Pacific 72, 50
- The reddest giants in M11 and NGC 7789
- 1960PASP...72...50W