A 1-Factorization of the Iterated Line Graphs of Regular Graphs
赵光复 · 中国科学通报：英文版 · 1993
Which graphs are 1-factorizable? In other words, which graphs are regular graphs of class 1? It is an interesting open problem. The importance and difficulty of this problem become apparent when we realize that the four-colour theorem holds if and only if every bridgeless 3-regular planar graph is 1-factorable. Jaeger proved that if a regular graph