References
- 1. U.S. Department of Health, Education and Welfare: Smoking and Health: Report of the Advisory Committee to the Surgeon General of the Public Health Service; U.S. Government Printing Office, Washington, 1964.
- 2. Hill, A.B.: The Environment and Disease: Association or Causation?; Proc. R. Soc. Med. 58 (1965) 295-300.