1. M. Behzad, Graphs and their chromatic number, Ph.D.Thesis, Michigan State University, 1965.
2. The total chromatic number of graphs of high minimum degree;Chetwynd;J. London Math. Soc.,1991
3. Some theorems on abstract graphs;Dirac;Proc. London Math. Soc.,1952
4. On the maximal number of disjoint circuits in a graph;Erdös;Publ. Math. Debrecen,1962
5. Recent result on the total chromatic number;Hilton;Discrete Math.,1993