  The identification of low-energy counterparts for gamma-ray sources is one of
the biggest challenge in modern gamma-ray astronomy. Recently, we developed and
successfully applied a new association method to recognize gamma-ray blazar
candidates that could be possible counterparts for the unidentified gamma-ray
sources above 100 MeV in the second Fermi Large Area Telescope (LAT) catalog
(2FGL). This method is based on the Infrared (IR) colors of the recent
Wide-Field Infrared Survey Explorer (WISE) all-sky survey. In this letter we
applied our new association method to the case of unidentified INTEGRAL sources
(UISs) listed in the fourth soft gamma-ray source catalog (4IC). Only 86 UISs
out of the 113 can be analyzed, due to the sky coverage of the WISE Preliminary
data release. Among these 86 UISs, we found that 18 appear to have a gamma-ray
blazar candidate within their positional error region. Finally, we analyzed the
SWIFT archival data available for 10 out these 18 gamma-ray blazar candidates,
and we found that 7 out of 10 are clearly detected in soft X-rays and/or in the
optical-ultraviolet band. We cannot confirm the associations between the UISs
and the selected gamma-ray blazar candidates due to the discrepancies between
the INTEGRAL and the soft X-ray spectra. However, the discovery of the soft
X-ray counterparts for the selected gamma-ray blazar candidates adds an
important clue to help understand their origin and to confirm their blazar
nature.
