Columbia subject headings:
Harvard subject headings:
Balkan Peninsula--Foreign relations--1989---Congresses.
Balkan Peninsula--Foreign relations--Greece--Congresses.
Greece--Foreign relations--1974---Congresses.
Greece--Foreign relations--Balkan Peninsula--Congresses.
Nationalism--Balkan Peninsula--Congresses.
Princeton subject headings:
Balkan Peninsula--Foreign relations--1989---Congresses.
Balkan Peninsula--Foreign relations--Greece--Congresses.
Greece--Foreign relations--1974---Congresses.
Greece--Foreign relations--Balkan Peninsula--Congresses.
Nationalism--Balkan Peninsula--Congresses.