Columbia subject headings:
Greece--Foreign relations--Congresses.
History, Ancient--Congresses.
International relations--Congresses.
Middle East--Foreign relations--Congresses.
Rome--Foreign relations--Congresses.
Harvard subject headings:
Civilization, Classical--Congresses
Civilization, Greco-Roman--Congresses
International relations and culture--History--Congresses.
International relations--History--Congresses.
Mediterranean Region--Civilization--Political aspects--Congresses.
Middle East--Civilization--To 622--Congresses.
Princeton subject headings:
Greece--Foreign relations--Congresses.
History, Ancient--Congresses.
International relations--Congresses.
Middle East--Foreign relations--Congresses.
Rome--Foreign relations--Congresses.