Columbia subject headings:
Mexico--Foreign relations--1970-1988.
Mexico--Foreign relations--United States.
Petroleum industry and trade--Mexico--History--20th century.
Petroleum products--Prices--Mexico--History--20th century.
United States--Foreign relations--Mexico.
Harvard subject headings:
Mexico--Foreign relations--1970-1988.
Mexico--Foreign relations--United States.
Petroleum industry and trade--Mexico--History--20th century.
Petroleum products--Prices--Mexico--History--20th century.
United States--Foreign relations--Mexico.
Princeton subject headings:
Mexico--Foreign relations--1970-1988.
Mexico--Foreign relations--United States.
Petroleum industry and trade--Mexico--History--20th century.
Petroleum products--Prices--Mexico--History--20th century.
United States--Foreign relations--Mexico.