• 1 Journals, Magazines, Newspapers

• 1 DVDs

• 23 Environmental aspects
• 16 Research
• 13 Effect of environment on
• 13 Human beings
• 12 Biology
• 12 Technology
• 11 Methodology
• 11 Vocational guidance
• 10 Geology
• 10 Physics
• 9 Chemistry
• 9 Conservation of natural resources
• 8 Ecology
• 8 Science
• 8 Sociology
• 7 Experiments
• 7 Industrial applications
• 7 Physical geography
• 5 Environmental protection
• 5 Natural resources
• 4 Anthropology
• 4 Biodiversity
• 4 Biotic communities

• 62 Films Media Group
• 45 Films for the Humanities & Sciences (Firm)
• 13 Annenberg Learner (Firm)
• 13 Infobase
• 8 Cambridge Educational (Firm)
• 7 Encyclopaedia Britannica, Inc.
• 6 Public Broadcasting Service (U.S.)
• 5 Video Education Australasia
• 4 Media Policy Center (Firm)
• 4 Uniview Worldwide
• 3 Andersen, Paul
• 3 Bozeman Science
• 3 Rafferty, John P.
• 3 Sinnott, Matt
• 2 Alexander Street Press
• 2 BBC Worldwide Ltd
• 2 Canadian Broadcasting Corporation
• 2 German United Distributors
• 2 Glasshead Productions
• 2 Petruzzello, Melissa
• 2 System TV (Firm)
• 2 Visual Education Centre
• 1 4 Learning (Firm)
• 1 ABC Commercial
• 1 ABC International

• 81 English

• 13 Earth (Planet)
• 7 United States
• 2 Great Britain
• 1 Michigan

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