  Optical spectroscopic identification of the nature of 21 unidentified
southern hard X-ray objects is reported here in the framework of our campaign
aimed at determining the nature of newly-discovered and/or unidentified sources
detected by INTEGRAL. Our results show that 5 of these objects are magnetic
Cataclysmic Variables (CVs), 4 are High-Mass X-ray Binaries (HMXBs; one of
which is in the Large Magellanic Cloud) and 12 are Active Galactic Nuclei
(AGNs). When feasible, the main physical parameters for these hard X-ray
sources are also computed using the multiwavelength information available in
the literature. These identifications further underscore the importance of
INTEGRAL in the study of the hard X-ray spectrum of AGNs, HMXBs and CVs, and
the usefulness of a strategy of catalogues cross-correlation plus optical
spectroscopy to securely pinpoint the actual nature of the X-ray sources
detected with INTEGRAL.
