2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/73256A connected 3-valent plane graph, whose faces are $q$- or 6-gons only, is called a {\em graph $q_n$}. We classify all graphs $4_n$, which are isometric subgraphs of a $m$-hypercube $H_m$.18 pages, 25 drawingsCombinatoricstext