Rao, S. (1980). Combinatorics and graph theory: Proceedings of the symposium held at the Indian Statistical Institute, Calcutta, February 25-29, 1980. Springer-Verlag.

Rao, S.B. Combinatorics and Graph Theory: Proceedings of the Symposium Held at the Indian Statistical Institute, Calcutta, February 25-29, 1980. Berlin: Springer-Verlag, 1980.

Rao, S.B. Combinatorics and Graph Theory: Proceedings of the Symposium Held at the Indian Statistical Institute, Calcutta, February 25-29, 1980. Springer-Verlag, 1980.