Ramsey, L. W.

1948. Combat dance and range extension of Agkistrodon piscivorus leucostoma. Herpetologica, 4:228.

Richmond, M. D.

1952. Head bobbing in reptiles. Herpetologica, 8:38.

Rosenfeld, S., and Glass, S.

1940. The inhibiting effect of snake bloods upon the hemorrhagic action of viper venoms on mice. Amer. Jour. Med. Sci., 199:482-486.

Schmidt, K. P.

1946. On the zoogeography of the Holarctic region. Copeia, 1946:144-152.

Shaw, C. E.

1948. The male combat "dance" of some crotalid snakes. Herpetologica, 4:137-145.

1951. Male combat in American colubrid snakes with remarks on combat in other colubrid and elapid snakes. Herpetologica, 7(4):149-168.