Berkeley 20

Number of stars per data source

	Reference  275 :  276 stars

References

 275
Durgapal A.K., Pandey A.K., Mohan V.
(2001) Astron. Astrophys. 372, 71
Multicolour CCD photometry of old open clusters: King 5 and Be 20
2001A&A...372...71D