Columbia subject headings:
Iron and steel workers--Political activity--Germany--North Rhine-Westphalia.
Iron industry and trade--Germany--North Rhine-Westphalia--History--Sources.
Management--Employee participation--Germany--North Rhine-Westphalia--History--Sources.
Steel industry and trade--Germany--North Rhine-Westphalia--History--Sources.
Harvard subject headings:
Collective bargaining--Iron industry--Germany--Ruhr (Region)--History--20th century--Sources.
Collective bargaining--Steel industry--Germany--Ruhr (Region)--History--20th century--Sources.
Industrial relations--Germany--Ruhr (Region)--History--20th century--Sources.
Iron and steel workers--Germany--Ruhr (Region)--History--20th century--Sources.
Reconstruction (1939-1951)--Germany--Ruhr (Region)--Sources.
Princeton subject headings:
Iron and steel workers--Germany--North Rhine-Westphalia--Political activity.
Iron industry and trade--Germany--North Rhine-Westphalia--History--Sources.
Management--Employee participation--Germany--North Rhine-Westphalia--History--Sources.
Steel industry and trade--Germany--North Rhine-Westphalia--History--Sources.