log(R_BLR [cm]) as a function of the logarithm of the central black hole mass in units of solar mass. The black points represent the sources of Paper I sample; errors are also plotted for the sources showing reliable X-ray occultations and listed in Table 1. To support our assertion, we also show in green the points referring to AGN sources of the AGN black hole mass database (Bentz & Katz 2015). The two dashed blue lines depict the relationship , as defined in Eq. (1).