Cowan, D. F. 1980. Adaption, maladaption and disease. In: Reproductive Biology and Diseases of Captive Reptiles. Society for the Study of Amphibians and Reptiles, Contributions to Herpetology No. 1. Murphy, J. B. , Collins, J. T. (eds), 191-196. Meseraull Printing, Lawrence, KS.