Columbia subject headings:
Germany--Social conditions.
Middle class--Germany--History.
Harvard subject headings:
Middle class--Europe--History--19th century.
Middle class--Germany--History--19th century.
Princeton subject headings:
Europe--Intellectual life.
Germany--Intellectual life.
Middle class--Europe--History--19th century.
Middle class--Europe--Social conditions.
Middle class--Germany--History--19th century.
Middle class--Germany--Social conditions.