Columbia subject headings:
Germany--Economic conditions--19th century.
Germany--Economic conditions--20th century.
Technology--Germany--History--19th century.
Technology--Germany--History--20th century.
Harvard subject headings:
Germany--Economic conditions--19th century.
Germany--Economic conditions--20th century.
Industrialization--Germany--History--19th century.
Industrialization--Germany--History--20th century.
Technology--Germany--History--19th century.
Technology--Germany--History--20th century
Princeton subject headings:
Germany--Economic conditions--19th century.
Germany--Economic conditions--20th century.
Technology--Germany--History--19th century.
Technology--Germany--History--20th century.