NGC 3680

Number of stars per data source

	Reference  225 :  494 stars
	Reference  247 :  391 stars

225: Anthony-Twarog B.J., Heim E.A., Twarog B.A., Caldwell N.; (1991) Astron. J. 102, 1056; A BV photographic and CCD analysis of the intermediate-age open cluster, NGC 3680; 1991AJ....102.1056A
247: Platais V.K., Girard T.M., Platais I., van Altena W.F., Ianna P.A., Cannon R.D.; (1995) Astron. J. 109, 672; A proper-motion study of the open cluster NGC 3680; 1995AJ....109..672P