• 3 DVDs
• 1 VHS Videocassettes

• 2 Antiquities
• 1 Astronomy
• 1 Cave paintings
• 1 Climatic changes
• 1 Description and travel
• 1 Earth sciences
• 1 Effect of human beings on
• 1 Environmental protection
• 1 History
• 1 Mounds
• 1 Natural history
• 1 Natural resources
• 1 Nature
• 1 Ocean
• 1 Plate tectonics

• 2 Untamed Science (Firm)
• 1 Andorfer, Gregory
• 1 Barg, Steve
• 1 Belby, Colin
• 1 Blumentrit, Dylan
• 1 Bocher, Buzz
• 1 Carson, Eric
• 1 Cupp, Mark
• 1 Dan Bertalan
• 1 De Lancey, John, approximately 1741-1829
• 1 Finley-Holiday Film Corporation
• 1 Gartner, William (William G.)
• 1 Grabowska, John
• 1 Hawkhill Associates
• 1 Howe, George (Filmmaker)
• 1 Jacobson, Tim
• 1 Kester, Dave
• 1 Kiley, Richard
• 1 Kjome, Jordan
• 1 Larson, Daniel
• 1 Lay, Tim
• 1 Metropolitan Pittsburgh Public Broadcasting, inc
• 1 Mississippi Valley Conservancy
• 1 National Academy of Sciences (U.S.)
• 1 Nelson, Rob (Filmmaker)

• 2 Driftless Area
• 2 Wisconsin
• 1 Earth (Planet)
• 1 Great Lakes Region (North America)
• 1 Iowa
• 1 Kickapoo River (Wis.)
• 1 Minnesota
• 1 Niagara Escarpment
• 1 Sun
• 1 United States
• 1 Yellowstone National Park

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