1. Scientific adviser to the Consultative Group on International Agricultural Research, World Bank, Washington, D.C. 20433
2. Associate professor of geography, University of Florida, Gainesville 32611
3. Executive secretary to the International Board for Plant Genetic Resources, Via delle Terme di Caracalla, Rome 00100, Italy
4. Assistant executive secretary to the International Board for Plant Genetic Resources, Via delle Terme di Caracalla, Rome 00100, Italy