Columbia subject headings:
Austria--Foreign relations--Balkan Peninsula--Congresses.
Balkan Peninsula--Foreign relations--Austria--Congresses.
Balkan Peninsula--Politics and government--19th century--Congresses.
Balkan Peninsula--Politics and government--20th century--Congresses.
Eastern question (Balkan)--Congresses.
Harvard subject headings:
Austria--Foreign relations--Balkan Peninsula--Congresses.
Balkan Peninsula--Foreign relations--Austria--Congresses.
Balkan Peninsula--Politics and government--Congresses.
Eastern question (Balkan)--Congresses.
Princeton subject headings:
Austria--Politics and government--1848-1918--Congresses.
Eastern question (Balkan)--Congresses.
Yugoslavs--Congresses.