Superconducting transition temperature and other properties of thin metallic films

We point out that the results of (1) Shapoval, for the superconducting transition temperature of a thin film, (2) Nedorezov, for the surface contributions to the density of states, Fermi energy, and specific heat, and (3) Cooper and Hu, for the surface contribution to the density of states, are entirely unphysical because they are obtained from inconsistent models which violate the surface analog of the Friedel sum rule, $〈\gamma 〉=\frac{\pi }{4}$.