Columbia subject headings:
Harvard subject headings:
Partido Comunista Brasileiro--Influence--History.
Petroleum industry and trade--Brazil--History.
Petróleo Brasileiro, S.A.--History.
Princeton subject headings:
Partido Comunista Brasileiro--History.
Petroleum industry and trade--Government ownership--Brazil--History.
Petroleum industry and trade--Government policy--Brazil--History.
Petróleo Brasileiro, S.A.--History.