A note on vertex-criticality with respect to edge-coloring
Cailing Wang · International Journal of Mathematics & Statistics/International journal of mathematics and statistics · 2014
Multigraphs for which the chromatic index achieving the maximum degree are said to be Class 1, and otherwise they are Class 2. The problem of characterizing graphs of Class 1 or Class 2 is NP-hard, so it is natural to study graphs which are critical. There are a number of denitions of criticality concerning the chromatic index and some interesting problems arising from them. In this paper, we improve a result on the vertex criticality of edge-coloring of star multigraphs.