• 12 Natural resources
• 6 Environmental aspects
• 6 Environmental policy
• 6 Environmental protection
• 6 Government policy
• 6 Local transit
• 5 Energy consumption
• 5 Energy development
• 5 Management
• 5 Power resources
• 2 Business ethics
• 2 Moral and ethical aspects
• 1 Aeronautics
• 1 Architecture, Modern
• 1 Collective behavior
• 1 Congestion pricing
• 1 Food
• 1 Social movements
• 1 Stream restoration
• 1 Synthetic fuels
• 1 Transportation
• 1 Trucks

• 12 Films Media Group
• 12 Films for the Humanities & Sciences (Firm)
• 12 Infobase
• 1 Pollan, Michael

• 12 English

• 1 Brazil
• 1 California
• 1 India
• 1 London (England)
• 1 Portland (Or.)
• 1 Seoul (Korea)
• 1 South Asia

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