1. Permutation groups and almost regular graphs;Babai;Studia Sci. Math. Hungar.,1973
2. Algebraic Graph Theory;Biggs,1974
3. K. S. BOOTH, Isomorphism testing of graphs, semisroups and finite automata are polynomially equivalent problems, SIAM J. Comput., in press.
4. A four-gadget;Carter;SIGACT News,1977
5. The complexity of theorem-proving procedures;Cook,1970