1. World Energy Supplies 1969–1972, Statistical Papers Series J No 17, United Nations 1974. Copies can be obtained from HMSO, London.
2. World Power Conference Survey of Energy Resources;Parker,1962
3. World Power Conference Survey of Energy Resources;Parker,1968
4. World Energy Conference Survey of Energy Resources,1974
5. Summary Petroleum and Selected Mineral Statistics for 120 Countries, including Offshore Areas;Albers,1973