Columbia subject headings:
European cooperation--Congresses.
Poland--Relations--Ukraine--Congresses.
Regional planning--International cooperation--Congresses.
Regional planning--Poland--Congresses.
Regional planning--Ukraine--Congresses.
Ukraine--Relations--Poland--Congresses.
Harvard subject headings:
European cooperation--Congresses.
Poland--Relations--Ukraine--Congresses.
Regional planning--International cooperation--Congresses.
Regional planning--Poland--Congresses.
Regional planning--Ukraine--Congresses.
Ukraine--Relations--Poland--Congresses.
Princeton subject headings:
Poland--Relations--Ukraine--History.
Ukraine--Relations--Ukraine--History.