Comment on “Properly interpreting scanning tunneling microscopy images: the Cu(1 0 0)-c(2 × 2)N surface revisited” by T.E. Wofford, S.M. York and F.M. Leibsle [Surf. Sci. 522 (2003) 47]

The rationale for attributing the protrusions in STM images of Cu(1 0 0)c(2 × 2)-N to Cu atoms in a symmetry-reducing adsorbate-induced surface layer rumpling is restated, and the alternative explanation by Wofford et al. is refuted.