Comment on "Cusp relations for local strongly decaying properties in electronic systems" - art. no. 016501

In a recent paper [Phys. Rev. A 52, 2645 (1995)], Liu et al. presented an a pproach for obtaining physical properties at the nuclear cusps. They compar ed it with the Hiller-Sucher-Feinberg (HSF) identity [Phys. Rev. A 18, 2399 (1978)] and found theirs to be superior. It is shown here that this conclu sion is based on the comparison on equal footing of different types of iden tities, namely physical in the case of HSF and mathematical in the case of Liu et al.