• 85 Videos, Slides, Films

• 1 DVDs

• 81 Natural resources
• 52 Environmental sciences
• 42 Earth sciences
• 42 Geography
• 42 Landforms
• 42 Water-supply
• 40 Land use
• 32 Physical geography
• 16 Geology
• 13 Physical geology
• 12 Biotic communities
• 12 Ecological regions
• 11 Ecological zones
• 9 Technical education
• 8 Agricultural education
• 6 Agronomy
• 6 Life sciences
• 5 Earth (Planet)
• 5 Mantle
• 4 Agricultural implements
• 4 Agricultural machinery
• 4 Agriculture
• 4 Air
• 4 Biology

• 84 Films Media Group
• 81 Infobase
• 17 PBS (Firm)
• 13 Camille S. DeBose (Firm)
• 6 BBC (Firm)
• 6 Green Planet Films (Firm)
• 5 CINEFETE (Firm)
• 5 National Geographic Digital Media (Firm)
• 4 Global Screen (Firm)
• 3 Australian Broadcasting Corporation (Firm)
• 3 Cerebellum Corporation (Firm)
• 3 Kwanza (Firm)
• 2 Video Education America (VEA) (Firm)
• 1 A&E Networks (Firm)
• 1 American Geosciences Institute (Firm)
• 1 Bullfrog Films
• 1 CNN (Firm)
• 1 Canadian Broadcasting Corp. (Firm)
• 1 DCD Media (Firm)
• 1 Discovery Education (Firm)
• 1 EPF Media Group (Firm)
• 1 First Pond Entertainment (Firm)
• 1 Fogel, Anson
• 1 Forge Motion Pictures (Firm)
• 1 Journeyman Pictures (Firm)

• 85 English

• 3 Asia
• 2 North America
• 1 Africa, Sub-Saharan
• 1 Colorado River
• 1 Colorado River (Colo.-Mexico)
• 1 Colorado River Watershed
• 1 Colorado River Watershed (Colo.-Mexico)
• 1 Europe
• 1 India
• 1 South Asia

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