1. Barker, D.J.P. & G. Rose. 1976. Epidemiology in Medical Practice. Churchill Livingstone, New York. 79 pp.
2. Bogovski, P. 1972. The importance of the analysis of N-Nitroso compounds in international research. pp. 1–55 In: N-Nitroso Compounds Analysis and Formation (Ed. P. Bogovski, R. Preussman and E.J. Walker). IARC Sci. Publ. 3. Lyon.
3. Bogovski, P. & E.A. Walker. 1975. N-Nitroso compounds in the environment. IARC Sci. Publ. 9. Lyon.
4. Brooks, D. & 1. Cech. 1979. Nitrates and bacterial distribution in rural domestic water supplies. Water Res. 13:33–41.
5. Cannon, H.L. & H.C. Hopps. 1971. (Ed.) Environmental geochemistry in health and disease. Geol. Soc. Am. Mem. 123.