Ruprecht 91

Number of stars per data source

	Reference   50 :    2 stars
	Reference   51 :    5 stars
	Reference   57 :   14 stars
	Reference  180 :   15 stars

50: Cannon A.J., Pickering E.C.; (1918-1924), Ann. Obs. Harvard Coll. Obs. 91 to 99 and 100; Henry Draper catalogue and extension
51: Cannon A.J., Mayall W.M.; 1949) Ann. Harvard Coll. Obs. 112; Henry Draper extension 2
57: Loden L.O., Loden K., Nordstrom B., Sundman A.; (1976) Astron. Astrophys. Suppl. 23, 283; A spectral survey of the southern Milky Way III. O-B9 and M stars l=280d to 306d; 1976A&AS...23..283L
180: Turner D.G., Forbes D., van den Bergh S., Younger P.F., Berdnikov L.N.; (2005) Astron. J. 130, 1194; The open cluster Ruprecht 91 and its cepheids; 2005AJ....130.1194T