  Inclusive quasi-elastic electron scattering off nuclei is investigated at
high momentum transfer (Q^2>1 (GeV/c)^2) and x>1 adopting a consistent
treatment of nucleon-nucleon correlations in initial and final states. It is
shown that in case of light as well as complex nuclei the inclusive cross
section at 1.3<x<2 is dominated by the absorption of the virtual photon on a
pair of correlated nucleons and by their elastic rescattering in the continuum,
whereas at x>2 it is governed by the rescattering of the outgoing
off-mass-shell nucleon in the complex optical potential generated by the ground
state of the residual (A-1)-nucleon system.
