• 10 Agriculture
• 6 Study and teaching
• 5 Prevention
• 4 Primates
• 3 Cancer
• 3 History
• 3 Peasants
• 2 Agricultural extension work
• 2 Agricultural industries
• 2 Agricultural innovations
• 2 Biology
• 2 Clinical trials
• 2 Drug abuse
• 2 Drug use
• 2 Extension
• 2 Farming systems
• 2 Geography
• 2 Human experimentation in medicine
• 2 Marijuana
• 2 Medicine, Preventive
• 2 Methodology
• 2 Ruminants
• 2 Sociology
• 2 Wildlife conservation

• 3 National Institute on Drug Abuse
• 3 National Institutes of Health (U.S.)
• 2 Food and Agriculture Organization of the United Nations
• 2 National Cancer Institute (U.S.)
• 1 AGRARIA (Organization)
• 1 Agroecología Universidad Cochabamba
• 1 Alzérreca, Humberto
• 1 Ameghino Cabrejos, Enrique
• 1 American Association for the Advancement of Science
• 1 Arambulo, Primo V., 1941-
• 1 Assembly of Life Sciences (U.S.). Committee on Research Priorities in Tropical Biology
• 1 Ayaviri Nina, Dante
• 1 Berdegué, Julio
• 1 Caro, José Eusebio, 1817-1853
• 1 Castellanos, Alfredo
• 1 Castro Rodríquez, Napoleón [AACR2]
• 1 Centro Interuniversitario de Desarrollo Andino
• 1 Centro Peruano de Estudios Sociales
• 1 Cherin, Robin
• 1 Cohan, Hugo E
• 1 Combes, Hélène
• 1 Comisión de Ciencia y Tecnología (Ecuador)
• 1 Cooperative Research Project on Agricultural Technology in Latin America
• 1 Coulter, John
• 1 De Janvry, Alain

• 12 English
• 5 French
• 3 Portuguese
• 2 German
• 1 Italian
• 1 Russian
• 1 Unknown

• 9 United States
• 6 Latin America
• 4 Bolivia
• 4 Mexico
• 2 Andes Region
• 2 Central America
• 2 Peru
• 1 America
• 1 Andes
• 1 Argentina
• 1 Chile
• 1 Costa Rica
• 1 Developing countries
• 1 Ecuador
• 1 Panama
• 1 Spain
• 1 Tropics

• 7 Congresses
• 3 Bibliography
• 2 Handbooks, manuals, etc
• 1 Fiction
• 1 Imprints
• 1 Problems, exercises, etc
• 1 Readers
• 1 Union lists

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