NGC 6231

Number of stars per data source

	Reference  172 :  850 stars
	Reference  218 : 1050 stars

172: Sung H., Bessell M.S., Lee s.-W.; (1998) Astron. J. 115, 734; UBVRI Halpha photometry of the young open cluster NGC 6231; 1998AJ....115..734S
218: Baume G., Vazquez R.A., Feinstein A.; (1999) Astron. Astrophys. Suppl. 137, 233; UBVI imaging photometry of NGC 6231; 1999A&AS..137..233B