• 62 Videos, Slides, Films

• 19 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 Sociology
• 7 Industrial applications
• 7 Physical geography
• 6 Ecology
• 6 Experiments
• 5 Environmental protection
• 5 Natural resources
• 4 Anthropology
• 4 Biodiversity
• 4 Biotic communities
• 4 Business

• 45 Films for the Humanities & Sciences (Firm)
• 13 Annenberg Learner (Firm)
• 13 Infobase
• 8 Cambridge Educational (Firm)
• 6 Public Broadcasting Service (U.S.)
• 5 Video Education Australasia
• 4 Media Policy Center (Firm)
• 4 Uniview Worldwide
• 2 BBC Worldwide Ltd
• 2 Canadian Broadcasting Corporation
• 2 German United Distributors
• 2 System TV (Firm)
• 2 Visual Education Centre
• 1 4 Learning (Firm)
• 1 ABC International
• 1 ABC News Productions
• 1 Allegro Productions (Firm)
• 1 Carolina Bioloical Supply Co
• 1 Deutsche Welle
• 1 Filmoption International (Firm)
• 1 MacNeil/Lehrer Productions
• 1 National Geographic Television & Film
• 1 TED Conferences LLC
• 1 TV 2 (Denmark)

• 62 English

• 13 Earth (Planet)
• 6 United States

Limit year range