Columbia subject headings:
Harvard subject headings:
Germany--Social conditions--18th century.
Germany--Social conditions--19th century.
Germany--Social conditions--20th century.
Social mobility--Germany--History.
Working class--Germany--Biography.
Princeton subject headings:
Germany--Social conditions--18th century.
Germany--Social conditions--19th century.
Germany--Social conditions--20th century.
Social mobility--Germany--History.