NGC 2251

Number of stars per data source

	Reference  173 :    1 star
	Reference 1341 :   32 stars
	Reference 1385 :    3 stars
	Reference 2029 :    3 stars

References

 173
Hiltner W.A.
(1956) Astrophys. J. Suppl. 2, 389
Photometric polarization and spectrographic observations of O and B Stars
1956ApJS....2..389H
 1341
Hoag A.A., Johnson H.L., Iriarte B., Mitchell R.I., Hallam K.L., Sharpless S.
(1961) Publ. US. Nav. Obs. 17, 343
Photometry of stars in galactic cluster fields
1961PUSNO..17..343H
 1385
Eggen O.J.
(1968) Royal Obs. Bull. No. 137
Three-colour photmetry of 4000 northern stars
1968RGOB..137....1E
 2029
Celeste Parisi M., Claria J.J., Piatti A.E., Geisler D.
(2005) Mon. Not. R. Astron. Soc. 363, 1247
2005MNRAS.363.1247P