  We report the detection of two new gamma-ray sources in the Fermi-LAT sky
(Pass 8) at energies higher than 20 GeV, and confirmed at lower energies, using
a source detection tool based on the Minimum Spanning Tree algorithm. One of
these sources, at a Galactic latitude of about -4{\deg}, is a new discovery,
while the other was previously reported above 50 GeV in the 2FHL catalogue. We
searched for archival multi-wavelength data of possible counterparts and found
interesting candidates. Both objects are radio sources and their WISE infrared
colours are typical of blazars. While for the former source no optical spectra
are available, for the latter a puzzling optical spectrum corresponding to a
white dwarf star is found in the 6dF database. We discuss the spectral energy
distributions of both sources and possible interpretations.
