• 18 Videos, Slides, Films

• 11 Human geography
• 8 Conservation of natural resources
• 8 Effect of human beings on
• 8 Human ecology
• 8 Nature
• 7 Environmental protection
• 7 Social life and customs
• 7 Water
• 6 Environmental aspects
• 6 Environmental geography
• 6 International economic relations
• 6 Natural resources
• 6 Pollution
• 5 Hydrology
• 5 Landforms
• 5 Physical geography
• 5 Refuse and refuse disposal
• 5 Social ecology
• 5 Toxicology
• 5 Waste disposal
• 4 Economic geography
• 4 Population policy
• 4 Rural-urban migration

• 18 Films for the Humanities & Sciences (Firm)
• 6 Parthenon Entertainment (Firm)
• 4 Moyers, Bill D
• 4 Sunrise Media LLC
• 3 Network Ireland Television
• 1 Agency for Instructional Technology
• 1 American Public Television
• 1 German United Distributors
• 1 Journeyman Pictures (Firm)
• 1 WNET (Television station : New York, N.Y.)

• 18 English
• 2 Spanish

• 5 United States
• 3 China
• 1 Africa
• 1 Africa, North
• 1 Amazon River
• 1 Asia
• 1 Bolivia
• 1 Costa Rica
• 1 East Asia
• 1 Ecuador
• 1 Europe
• 1 Guatemala
• 1 India
• 1 Latin America
• 1 Mexico
• 1 Peru
• 1 South America
• 1 South Asia

Limit year range