Colouring of generalized signed planar graphs

Ligang Jin, Tsai-Lien Wong, Xuding Zhu

Assume $G$ is a graph. We view $G$ as a symmetric digraph, in which each edge $uv$ of $G$ is replaced by a pair of opposite arcs $e=(u,v)$ and $e^{-1}=(v,u)$. Assume $S$ is an inve…