On the identification of the Fermi/LAT source 0FGL J2001.0+4352 with a
  BL Lac
  We report on the identification of the gamma-ray source 0FGL J20001.0+4352
listed in the Fermi bright source catalogue. This object, which has an observed
1-100 GeV flux of (7.8 +/- 1.2) x 10^{-9} ph cm^{-2} s^{-1} and is located
close to the Galactic plane, is not associated with any previously known high
energy source. We use archival XMM-Newton and Swift/XRT data to localise with
arcsec accuracy the X-ray counterpart of this GeV emitter and to characterise
its X-ray properties: the source is bright (the 0.2-12 keV flux is 1.9 x
10^{-12} erg cm^{-2} s^{-1}), variable (by a factor of ~2) and with a steep
power law spectrum (Gamma = 2.7). It coincides with a radio bright (~200 mJy at
8.4 GHz) and flat spectrum object (MG4 J200112+4352 in NED). Broad-band optical
photometry of this source suggests variability also in this waveband, while a
spectroscopic follow-up observation provides the first source classification as
a BL Lac object. The source SED, as well as the overall characteristics and
optical classification, point to a high frequency peaked blazar identification
for 0FGL J2001.0+4352.
