2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/60653In this short notice we give a universal definition of $\Z_2$-module $Or(Γ)$ of orientations of a graph $Γ$ and construct a method, by means of which one can easily verify whenever two such special definitions coincide.AmS LaTeX, 5 pagesCombinatorics05C75; 94C15text