  The 4th IBIS/ISGRI survey lists 723 hard X-ray sources many still
unidentified. We cross-correlated the list of the sources included in the 4th
IBIS catalogue with the Swift/XRT data archive, finding a sample of 20 objects
for which XRT data could help in the search for the X-ray and hence optical
counterpart and/or in the study of the source spectral and variability
properties below 10 keV. Four objects (IGR J00465-4005, LEDA 96373, IGR
J1248.2-5828 and IGR J13107-5626) are confirmed or likely absorbed active
galaxies, while two (IGR J14080-3023 and 1RXS J213944.3+595016) are unabsorbed
AGN. We find three peculiar extragalactic objects, NGC 4728 being a Narrow Line
Seyfert galaxy, MCG+04-26-006 a type 2 LINER and PKS 1143-693 probably a QSO;
furthermore, our results indicate that IGR J08262+4051 and IGR J22234-4116 are
candidate AGN, which require further optical spectroscopic follow-up
observations to be fully classified. In the case of 1RXS J080114.6-462324 we
are confident that the source is a Galactic object. For IGR J10447-6027, IGR
J12123-5802 and IGR J20569+4940 we pinpoint one X-ray counterpart, although its
nature could not be assessed despite spectral and sometimes variability
information being obtained. Clearly, we need to perform optical follow-up
observations in order to firmly assess their nature. There are five objects for
which we find no obvious X-ray counterpart (IGR J07506-1547 and IGR
J17008-6425) or even no detection (IGR J17331-2406, IGR J18134-1636 and IGR
J18175-1530); apart from IGR J18134-1636, all these sources are found to be
variable in the IBIS energy band, therefore it is difficult to catch them even
in X-rays.
