Trumpler 18

Number of stars per data source

	Reference  256 :    4 stars
	Reference  470 :    1 star
	Reference  487 :    1 star
	Reference  514 :    3 stars

256: Johansson K.L.V.; (1980) Astron. Astrophys. Suppl. 41, 43; Colour excess and stellar distribution in five selected directions of the Milky Way in Carina, Crux, Centaurus and Norma; 1980A&AS...41...43J
470: Knude J.; (1992) Astron. Astrophys. Suppl. 92, 841; uvby Beta observations of 528 type B stars with V between the 8th and 9th magnitude; 1992A&AS...92..841K
487: Kaltcheva N.T., Georgiev L.N.; (1993) Monthly Notices Roy. Astron. Soc. 261, 847; Stromgren and HBeta photometry of OB associations and open clusters - II. Tr 16 and Car OB2; 1993MNRAS.261..847K
514: Shobbrook R.R., Lynga G.; (1994) Monthly Notices Roy. Astron. Soc. 269, 857; uvby - Beta photometry of 100 stars in the region of eta Carina; 1994MNRAS.269..857S