• 53 Videos, Slides, Films

• 52 Conservation of natural resources
• 30 Recycling (Waste, etc.)
• 30 Renewable energy sources
• 28 Endangered species
• 18 Biodiesel fuels
• 14 Climatic changes
• 8 Solar energy
• 6 Wildlife conservation
• 4 Environmental education
• 2 Pollution
• 1 Galilei, Galileo, 1564-1642
• 1 Research

• 52 Holmes, Abbe
• 24 Alexander Street Press
• 1 Dorslar, Marianne Van
• 1 Roberts, Paul
• 1 World Wide Entertainment (Firm)

• 53 Documentary films
• 24 Internet videos

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