1. Brittain, R. P. (1968) "The Sexual Asphyxias', in Gradwohl's Legal Mediane, 2nd edn, ed. F. E. Camps. Bristol: Wright, p. 549.
2. Busch, K. A. and Cavanagh, J. R. (1986) "The Study of Multiple Murder: Preliminary Examination of the Interface between Epistemology and Methodology'. Journal of Interpersonal Violence 1(1): 5-23.
3. Dickinson, A. (1980) Contemporary Animal Learning Theory. Cambridge: Cambridge University Press.
4. East, Norwood (1949) Society and the Criminal. London: HMSO.
5. Ellis, H. (1933) Psychology of Sex: a Manual for Students, 2nd edn. London: Heinemann (Medical Books).