Columbia subject headings:
Balkan Peninsula--Foreign relations--United States.
Balkan Peninsula--Relations--United States.
Europe, Eastern--Relations--United States.
United States--Foreign relations--Balkan Peninsula.
United States--Relations--Balkan Peninsula.
United States--Relations--Europe, Eastern.
Harvard subject headings:
Balkan Peninsula--Foreign relations--United States.
United States--Foreign relations--Balkan Peninsula.
Princeton subject headings:
Balkan Peninsula--Foreign relations--United States.
Balkan Peninsula--Relations--United States.
Europe, Eastern--Relations--United States.
United States--Foreign relations--Balkan Peninsula.
United States--Relations--Balkan Peninsula.
United States--Relations--Europe, Eastern.