• 6 Videos, Slides, Films

• 6 DVDs

• 3 Volcanoes
• 2 History
• 1 Animals
• 1 Asteroids
• 1 Collisions with Earth
• 1 Continental drift
• 1 Effect of human beings on
• 1 Endangered species
• 1 Environmental aspects
• 1 Environmental conditions
• 1 Forest fires
• 1 Historical geology
• 1 National parks and reserves
• 1 Nature
• 1 Plate tectonics
• 1 Reintroduction
• 1 Snowmobiles
• 1 Supervolcanoes
• 1 Trenches
• 1 Tsunamis
• 1 Volcanic eruptions
• 1 Waterfalls
• 1 Wildlife reintroduction
• 1 Wolves

• 3 Arts and Entertainment Network
• 3 New Video Group
• 2 History Channel (Television network)
• 1 Armstrong, Brian
• 1 British Broadcasting Corporation
• 1 Canfor-Dumas, Edward
• 1 Discovery Channel (Firm)
• 1 Discovery Communications, Inc
• 1 Greystone Communications
• 1 Gruppo Mediaset (Italy)
• 1 Hess, Janet
• 1 Hicklin, William
• 1 History (Television network)
• 1 Johnson, Corey, 1961-
• 1 Johnston, Shaun
• 1 Landis, Bob, 1940-
• 1 Lewis, Gary, 1958-
• 1 Mitchell, Tony
• 1 Mudd, Roger, 1928-2021
• 1 National Geographic Channel (Television station : Washington, D.C.)
• 1 National Geographic Society (U.S.)
• 1 National Geographic Television
• 1 National Geographic Television & Film
• 1 Nihon Hōsō Kyōkai
• 1 Pioneer Productions

• 6 English

• 1 Alps
• 1 Atacama Desert (Chile)
• 1 Earth (Planet)
• 1 Great Lakes (North America)
• 1 Hawaii
• 1 Iceland
• 1 Idaho
• 1 Krakatoa (Indonesia)
• 1 Montana
• 1 Ness, Loch (Scotland)
• 1 New York (N.Y.)
• 1 Pacific Area
• 1 San Andreas Fault (Calif.)
• 1 Wyoming
• 1 Yellowstone National Park Region

• 5 Documentary television programs
• 4 Nature television programs
• 4 Video recordings for the hearing impaired
• 2 Science television programs
• 1 Disaster television programs
• 1 Drama
• 1 Made-for-TV movies
• 1 Television programs
• 1 Television series
• 1 Wildlife television programs

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