Columbia subject headings:
Harvard subject headings:
Labor movement--Mexico--History--20th century
Labor unions--Mexico--History--20th century.
Mexico--History--Revolution, 1910-1920.
Working class--Mexico--History--20th century.
Princeton subject headings:
Labor movement--Mexico--History--20th century.
Mexico--Politics and government--1910-1946.
Working class--Mexico--History--20th century.