2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/18056In cond-mat/0107371, Mendonca proposes that diffusion can change the universality class of a parity-conserving reaction-diffusion process. In this comment we suggest that this cannot happen, due to symmetry arguments. We also present numerical results from lattice simulations which support these arguments, and mention a previous result supporting this conclusion.6 pages, 2 figures. short comment. Misprints correctedStatistical Mechanicstext