We present a new evidence of the accretion disc in active galactic nuclei, by
examining the properties of the Ha emission line versus viewing angle, in a
sample of superluminal (SL) quasars. Both line velocity width (FWHM) and rest
equivalent width (EW) correlate with viewing angle. These correlations are
quantitatively consistent with a disc geometry for both the line and the
underlying continuum source.Comment: 18 pages with 6 figures, accepted for publication in MNRA