UBVRI Systems: Resolving Different Versions
M. S. Bessell · Publications of the Astronomical Society of the Pacific · 1995
The photometry of Landolt has been transformed onto the Cousins (SAAO) system by using polynomial fits to photometry of 230 common stars. The accuracy of the fits are within 0.01 mag for (B-V), (R-I), and (V-I) and 0.02 mag for (U-B). The BVRI photometry of Bessell and Weis has also been transformed.