  Within the framework of our program (running since 2004) of identification of
hard X-ray INTEGRAL sources through optical spectroscopy, we present the
results concerning the nature of 33 high-energy objects. The data were acquired
with the use of six telescopes of different sizes and from one on-line archive.
The results indicate that the majority of these objects (23 out of 33) are
active galactic nuclei (AGNs), whereas 10 are sources in the local Universe
with eight of which in the Galaxy and two in the Small Magellanic Cloud (SMC).
Among the identified AGNs, 13 are of Type 1 (i.e., with broad emission lines),
eight are of Type 2 (with narrow emissions only), and two are X-ray bright,
optically normal galaxies with no apparent nuclear activity in the optical. Six
of these AGNs lie at high redshift (z > 0.5). Concerning local objects, we
found that five of them are Galactic cataclysmic variables, three are high-mass
X-ray binaries (two of which lying in the SMC), one is a low-mass X-ray binary,
and one is classified as a flare star that is likely of RS CVn type. The main
optical properties and inferred physical characteristics of these sources are
presented and discussed.
