1. FAG Production Yearbook 1949
2. FAO Forestry Paper 1982 30 Tropical Forest Resources
3. The Global 2000 Report to the President of the United States Entering the 21st Century 1980 1
4. The Global 2000 Report to the President of the United States Entering the 21st Century 1980 2
5. UNASYLVA 32: 8 (1980).