Columbia subject headings:
Harvard subject headings:
Bohemia (Czech Republic)--History--Congresses.
Czechoslovakia--History--Congresses.
Poland--History--19th century--Congresses.
Poland--History--20th century--Congresses.
Princeton subject headings:
Bohemia (Czech Republic)--History--Congresses.
Czechoslovakia--History--Congresses.
Poland--History--19th century--Congresses.
Poland--History--20th century--Congresses.