Columbia subject headings:
Central America--Politics and government--1951-1979.
Mexico--Relations--United States.
United States--Relations--Mexico.
Harvard subject headings:
Central America--Economic conditions--Congresses.
Central America--Foreign relations--1979---Congresses.
Central America--Foreign relations--Mexico--Congresses.
Central America--Foreign relations--United States--Congresses.
Central America--Politics and government--Congresses.
Mexico--Foreign relations--Central America--Congresses.
United States--Foreign relations--Central America--Congresses.
Princeton subject headings:
Central America--Foreign relations--1979---Congresses.
Central America--Foreign relations--Mexico--Congresses.
Central America--Foreign relations--United States--Congresses.
Mexico--Foreign relations--Central America--Congresses.
United States--Foreign relations--Central America--Congresses.