Columbia subject headings:
Germany--Relations--Poland--Congresses.
Germany--Relations--Ukraine--Congresses.
Poland--Relations--Germany--Congresses.
Poland--Relations--Ukraine--Congresses.
Ukraine--Relations--Germany--Congresses.
Ukraine--Relations--Poland--Congresses.
Harvard subject headings:
Germany--Relations--Poland--Congresses.
Germany--Relations--Ukraine--Congresses.
Poland--Relations--Germany--Congresses
Poland--Relations--Ukraine--Congresses.
Ukraine--Relations--Germany--Congresses.
Ukraine--Relations--Poland--Congresses.
Princeton subject headings:
Germany--Relations--Poland--Congresses.
Germany--Relations--Ukraine--Congresses.
Poland--Relations--Germany--Congresses.
Poland--Relations--Ukraine--Congresses.
Ukraine--Relations--Germany--Congresses.
Ukraine--Relations--Poland--Congresses.