Sub-arcsecond radio and optical observations of the likely counterpart   to the gamma-ray source 2FGL J2056.7+4939
  We have searched and reviewed all multi- wavelength data available for the region towards the gamma-ray source 2FGL J2056.7+4939 in order to con- strain its possible counterpart at lower energies. As a result, only a point-like optical/infrared source with flat-spectrum radio emission is found to be consistent with all X-ray and gamma-ray error circles. Its struc- ture is marginally resolved at radio wavelengths at the sub-arcsecond level. An extragalactic scenario appears to be the most likely interpretation for this object. 
J. Mart\'i, P. L. Luque-Escamilla, E. S\'anchez-Ayaso and A. J.   Mu\~noz-Arjonilla
astro-ph.HE