Columbia subject headings:
Elections--Mexico.
Partido de la Revolución Democrática (Mexico)
Political parties--Mexico.
Harvard subject headings:
Princeton subject headings:
Mexico--Politics and government--1988-2000.
Mexico--Politics and government--2000-
Partido de la Revolución Democrática (Mexico)--History--20th century.
Partido de la Revolución Democrática (Mexico)--History--21st century.
Political parties--Mexico--History--20th century.
Political parties--Mexico--History--21st century.