• 44 Videos, Slides, Films

• 27 Internal structure
• 16 Physical geography
• 15 Geology, Structural
• 15 Mantle
• 14 History
• 14 Natural resources
• 13 Historical geology
• 13 Plate tectonics
• 10 Geology
• 9 Hydrology
• 7 Environmental aspects
• 6 Power resources
• 6 Volcanoes
• 5 Energy consumption
• 5 Energy development
• 5 Landforms
• 5 Management
• 5 Water
• 4 Geography
• 4 Geomorphology
• 4 Submarine geology
• 3 Chemical elements
• 3 Chemistry, Physical and theoretical
• 3 Ecology
• 3 Ecosystem management

• 44 Films Media Group
• 4 BBC Worldwide Ltd
• 4 Cambridge Educational (Firm)
• 3 Allegro Productions (Firm)
• 3 Infobase
• 2 Granada Media (Firm)
• 2 Public Broadcasting Service (U.S.)
• 2 Video Education Australasia
• 1 ABC International
• 1 Academic Media (Firm)
• 1 American Museum of Natural History
• 1 BBC Worldwide Americas, Inc
• 1 CNBC (Television network)
• 1 EBS Trust (Firm)
• 1 Ethical Markets Media
• 1 Journeyman Pictures (Firm)
• 1 Meridian Education Corporation
• 1 National Geographic Television & Film
• 1 Québec/Amérique International
• 1 Visual Education Centre

• 44 English

• 1 California
• 1 Death Valley (Calif. and Nev.)
• 1 Hawaii
• 1 Iceland
• 1 Indian Ocean Region
• 1 Indonesia
• 1 Italy
• 1 Krakatoa
• 1 Krakatoa (Indonesia)
• 1 Middle East
• 1 Rocky Mountains
• 1 Solar system
• 1 Vesuvius (Italy)
• 1 Yellowstone National Park
• 1 Yosemite National Park (Calif.)
• 1 Yosemite National Park Region (Calif.)

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