2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/163107A proof that every outerplanar graph is Δ+2 colorable. This is slightly stronger then an unpublished result of Wang Shudong, Ma Fangfang, Xu Jin, and Yan Lijun proving the same for 2-connected outerplanar graphs.added reference to bounds for planar and higher genus graphsCombinatorics05C15text