Columbia subject headings:
Harvard subject headings:
Germany--Economic conditions--20th century.
Industries--Germany
Spethmann, Dieter.
Princeton subject headings:
August Thyssen-Hütte (Firm)--History.
Businessmen--Germany--Biography.
Germany--Economic conditions--20th century.
Industrialists--Germany--Biography.
Spethmann, Dieter.
Steel industry and trade--Germany--History.
Thyssen Krupp AG--History.