Columbia subject headings:
Wages--Miners--Germany--Ruhr (Region)--History--20th century.
Harvard subject headings:
Wages--Miners--Germany--Ruhr (Region)--History--20th century.
Princeton subject headings:
Labor unions--Germany (West)--Ruhr (Region)--History.
Ruhr (Germany : Region)--Economic policy--History.
Wage-price policy--Germany (West)--Ruhr (Region)--History.
Wages--Government policy--Germany (West)--Ruhr (Region)--History.