Columbia subject headings:
Harvard subject headings:
Germany--Economic conditions--19th century--Congresses.
Germany--Economic conditions--20th century--Congresses.
Germany--Economic conditions--21st century--Congresses.
Princeton subject headings:
Germany--Economic conditions--19th century--Congresses.
Germany--Economic conditions--20th century--Congresses.
Germany--Economic conditions--21st century--Congresses.