1. Horiuchi, S. 1992. Stagnation in the decline of the world population growth rate during the 1980s. Science 257, 761–765.
2. United Nations Population Fund. 1991. Population, Resources and the Environment, United Nations, NY.
3. Homer-Dixon, T.F. 1991. India’s population growth rate has leveled off at 2.1%/year and China’s at 1.3%/year. On the threshold: environmental changes as causes of acute conflict. Inter. Sec. 16, 76–116.
4. Long-range World Population Projections. Department of International and Economic and Social Affairs. United Nations, New York, 1992, Document Number ST/ESA/ SER.A/125.
5. World Watch Institute. 1990. State of The World 1990. Washington. The 430 M ha estimated to have been abandoned during a 40 year period is further confirmed by the World Resources Institute’s estimation that 10 M ha/yr of cropland is lost by erosion.