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