Columbia subject headings:
Renewable energy sources--Law and legislation--United States.
Harvard subject headings:
Coal--Research--Law and legislation--United States.
Energy development--Law and legislation--United States
Federal aid to energy development--United States.
Renewable energy sources--Law and legislation--United States
Princeton subject headings:
Coal--Research--Law and legislation--United States.
Energy development--Law and legislation--United States.
Federal aid to energy development--United States.
Renewable energy sources--Law and legislation--United States.