Columbia subject headings:
Harvard subject headings:
Germany--Foreign relations--Poland--Congresses.
Nationalism--Germany--Congresses.
Nationalism--Poland--Congresses.
Poland--Foreign relations--Germany--Congresses.
Princeton subject headings:
Germany--Foreign relations--Poland--Congresses.
Nationalism--Germany--Congresses.
Nationalism--Poland--Congresses.
Poland--Foreign relations--Germany--Congresses.