The paper by Pan et al, cond-mat/0107347, reports the discovery of 'electronic inhomogeneity' and 'spatial variations in the local density of states' in high $T_c$ cuprates. In my paper ``Effect of local potential variations in the model of hole superconductivity'', Physica C {\bf 194}, 119 (1992), many of the findings of Pan et al were foreshadowed.