Columbia subject headings:
Germany--Relations--Poland--Exhibitions.
Poland--Relations--Germany--Exhibitions.
Prussia (Germany)--History--Exhibitions.
Harvard subject headings:
Germany--Relations--Poland--Exhibitions.
Poland--Relations--Germany--Exhibitions.
Prussia (Germany)--History--Exhibitions.
Princeton subject headings:
Germany--Relations--Poland--Exhibitions.
Poland--Relations--Germany--Exhibitions.
Prussia (Germany)--History--Exhibitions.