Columbia subject headings:
Nonrenewable natural resources--Congresses.
Petroleum industry and trade--Economic aspects--Congresses.
Harvard subject headings:
Nonrenewable natural resources--Congresses.
Petroleum industry and trade--Economic aspects--Congresses.
Princeton subject headings:
Nonrenewable natural resources--Economic aspects--Congresses.
Petroleum industry and trade--Economic aspects--Congresses.