Columbia subject headings:
Harvard subject headings:
Geopolitics--Europe--Congresses.
Geopolitics--Study and teaching--Congresses.
History--Study and teaching--Congresses
International relations--Congresses
International relations--Study and teaching--Congresses.
World history--Congresses.
Princeton subject headings:
Geopolitics--Europe--Congresses.
Geopolitics--Study and teaching--Congresses.
History--Study and teaching--Congresses.
International relations--Congresses.
International relations--Study and teaching--Congresses.
World history--Congresses.