The non-variable stars brighter than 5.0 mag in the equatorial zone between declinations +10{deg} and -10{deg} were adopted by IAU Commission 25 in 1970 as primary standards for the Johnson and Morgan UBV system of 1966. Fainter HR stars in the same zone were chosen as secondary standards. Data for the primary standards are taken from a Cape Royal Observatory Mimeogram and are presented in table2.dat. It gives the weighted mean V magnitudes and B-V colors based upon the best series available up to the end of 1966. The table is believed to provide a consistent UBV system over the southern sky. Most of the secondary standard star data, given in table4.dat, were published in Mon. Notes Astron. Soc. S. Afr. (22,23).

Cone search capability for table II/50/ubv (Photometric standard stars)