1. GLOBOCAN 2000 [database online]. International Agency for Research on Cancer, Lyon, France. Cancer incidence, mortality and prevalence worldwide. Database version 1.0 (built November 30, 2000).
2. Food and Agricultural Organization of the United Nations, Rome, Italy,2003
3. Oxford Essential World Atlas,2001
4. Erythernal UV Index–Yearly average (2000). Tropospheric Emission Monitoring Internet Service,2004
5. Environmental factors and cancer incidence and mortality in different countries, with special references to dietary practices;Armstrong;Int J Cancer,1975