Comparison between our apparent integrated U, B, and V magnitudes and those in the Hyperleda (top panels), the RC3 (de Vaucouleurs et al. 1991) (middle panels), and the CGS (Ho et al. 2011; Li et al. 2011) (bottom panels) catalogs. Magnitudes are given in the [AB] system. Error bars of the Hyperleda and the RC3 U [AB] magnitudes account for an additional ±0.23 mag to include the uncertainty in the conversion from Vega to [AB] magnitudes. Magnitudes are not corrected for Galactic extinction.