A characterization of $4$-${\chi }_{\rho }$-(vertex-)critical graphs

Jasmina Ferme

Given a graph $G$, a function $c:V(G)⟶\{1,\dots ,k\}$ with the property that $c(u)=c(v)=i$ implies that the distance between $u$ and $v$ is greater than $i$, is call…