1. Corbett, T. H. 1977.Cancer and Chemicals, 21Chicago: Nelson-hall.
2. ASPH. 1986.Proposed National Strategies for the Prevention of Leading Work-related Diseases and Injuries, 35–48. Washington, DC: The Association of Schools of Public Health.
3. ACGIH. Threshold Limit Values and Biological Exposure Indices for 1986–87. American Conference of Governmental Industrial Hygienists. Cincinnati, OH.