  We report the first observation of azimuthal beam-spin asymmetries in hard
electroproduction of real photons off nuclei. Attributed to the interference
between the Bethe-Heitler process and the deeply-virtual Compton scattering
process, the asymmetry gives access to the latter at the amplitude level. This
process appears to be the theoretically cleanest way to access generalized
parton distributions. The data presented here have been accumulated by the
HERMES experiment at DESY, scattering the HERA 27.6 GeV positron beam off
deuterium and neon gas targets.
