Columbia subject headings:
Petroleum industry and trade--Brazil.
Petroleum--Brazil.
Harvard subject headings:
Oil and gas leases--Brazil.
Petroleum in submerged lands--Brazil.
Petroleum industry and trade--Brazil
Petroleum industry and trade--Economic aspects--Brazil.
Petroleum industry and trade--Government policy--Brazil.
Petroleum--Brazil.
Princeton subject headings:
Oil and gas leases--Brazil.
Petroleum in submerged lands--Brazil.
Petroleum industry and trade--Economic aspects--Brazil.
Petroleum industry and trade--Government policy--Brazil.