Columbia subject headings:
Elections--Mexico.
Mexico--Politics and government--1970-1988.
Mexico--Politics and government--1988-2000.
Harvard subject headings:
Elections--Mexico
Mexico--Politics and government--1970-1988.
Mexico--Politics and government--1988-
Princeton subject headings:
Elections--Mexico.
Mexico--Politics and government--1970-1988.
Mexico--Politics and government--1988-2000.