RXJ 0921+4529: a binary quasar or gravitational lens?
  We report the new spectroscopic observations of the gravitational lens RXJ
021+4529 with the multi-mode focal reducer SCORPIO of the SAO RAS 6-m
telescope. The new spectral observations were compared with the previously
observed spectra of components A and B of RXJ 0921+4529, i.e. the same
components observed in different epochs. We found a significant difference in
the spectrum between the components that cannot be explained with microlensing
and/or spectral variation. We conclude that RXJ 0921+4529 is a binary quasar
system, where redshifts of quasars A and B are 1.6535 +/- 0.0005 and 1.6625 +/-
0.0015, respectively.
