Columbia subject headings:
Labor unions--United States--History.
Working class--United States.
Harvard subject headings:
Labor unions and communism--United States--History--20th century.
Labor unions--United States--History--20th century
Women labor union members--United States--History--20th century.
Princeton subject headings:
Labor unions and communism--United States--History--20th century.
Labor unions--United States--History--20th century.
Women labor union members--United States--History--20th century.