Columbia subject headings:
Harvard subject headings:
Labor movement--Germany--History--20th century
Labor movement--Great Britain--History--20th century.
Labor unions--Germany--History--20th century
Labor unions--Great Britain--History--20th century.
Princeton subject headings:
Labor movement--Germany--History--20th century.
Labor movement--Great Britain--History--20th century.
Labor unions--Germany--History--20th century.
Labor unions--Great Britain--History--20th century.