Let p be a prime. It was shown by Folkman (J. Combin. Theory 3 (1967) 215) that a regular edge-transitive graph of order 2p or 2p is necessarily vertex-transitive. In this paper an extension of hisâ€¦ (More)

A Cayley graphX = Cay(G, S) of groupG is said to be normal ifR(G) is normal in Aut(X). Let G = ã€ˆa, b | an = b2 = 1ã€‰, S be a generating set of G, |S| = 4. In this paper we show that any one-regularâ€¦ (More)

For a group T and a subset S of T , the bi-Cayley graph BCay(T, S) of T with respect to S is the bipartite graph with vertex set TÃ—{0, 1} and edge set {{(g, 0), (sg, 1)} | g âˆˆ T, s âˆˆ S}. In thisâ€¦ (More)

A regular cover of a graph is said to be an edge-transitive cover if the fibre-preserving automorphism subgroup acts edge-transitively on the covering graph. In this paper we classify edge-transitiveâ€¦ (More)

A regular graph is called semisymmetric if it is edge transitive but not vertex transitive It is proved that the Gray graph is the only cubic semisymmetric graph of order p where p is a prime