&Extragalactic Astronomy BRussian Kgalaxies, RFGC catalogue// We apply the linear Eulerian version of the well-known POTENT method to the sample from the flat galaxies catalogue RFGC, with known radial peculiar velocities, in order to verify the extent to which the catalogue can be used by methods of mass density reconstruction. In the resulting mass density field one can identify such well-known large-scale structures as the Great Attractor, Perseus — Pisces supercluster, and the center of the Local Supercluster. This allows one to consider the result of the verification as being generally positive, which makes the non-linear Lagrangian version of the POTENT method promising for applying to the catalogue with the object of a more precise mass density reconstruction.