• 12 Historical geology
• 11 Study and teaching
• 9 History
• 9 Plate tectonics
• 7 Anthropology
• 7 Biology
• 7 Environmental sciences
• 7 Methodology
• 7 Research
• 6 Chemistry
• 6 Physics
• 5 Experiments
• 5 Internal structure
• 4 Crime
• 4 Ecosystem management
• 4 Politics and government
• 4 Psychology
• 4 Social control
• 4 Sociology
• 3 Evolution
• 3 Geomorphology
• 3 Human beings
• 3 Mathematics

• 20 Films Media Group
• 20 Films for the Humanities & Sciences (Firm)
• 4 National Geographic Television & Film
• 4 Uniview Worldwide
• 3 BBC Worldwide Ltd
• 3 Cambridge Educational (Firm)
• 1 Infobase

• 20 English

• 5 Earth (Planet)
• 4 United States
• 1 Arizona
• 1 Atacama Desert
• 1 Atacama Desert (Chile)
• 1 California
• 1 Chile
• 1 Death Valley (Calif. and Nev.)
• 1 Grand Canyon (Ariz.)
• 1 Hawaii
• 1 North America
• 1 Rocky Mountains
• 1 Sahara
• 1 Yellowstone National Park
• 1 Yosemite National Park (Calif.)
• 1 Yosemite National Park Region (Calif.)

• 20 Internet videos
• 17 Videorecording
• 15 Video recordings for the hearing impaired
• 3 Video recording

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