Columbia subject headings:
Elections--Mexico--Sonora (State)--History--20th century.
Sonora (Mexico : State)--Politics and government.
Harvard subject headings:
Elections--Mexico--Sonora (State)--History--20th century.
Sonora (Mexico : State)--Politics and government.
Princeton subject headings:
Elections--Mexico--Sonora (State)--History--20th century.
Sonora (Mexico : State)--Politics and government.