On the Classification Scheme for Phenomenological Universalities in Growth Problems in Physics and Other Sciences

Comment on "Classification Scheme for Phenomenological Universalities in Growth Problems in Physics and Other Sciences" by P. Castorina, P. P. Delsanto and C. Guiot, Phys. Rev. Lett. {\bf 96}, 188701 (2006) is presented. It has been proved that the West-like function of growth derived by the authors is incorrect and the approach does not take into account the growth of the biological systems undergoing atrophy or demographic and economic systems undergoing involution or regression. A simple extension of the model, which permits derivation of the so far unknown involuted Gompertz function of growth is proposed.