Columbia subject headings:
Harvard subject headings:
Austria--History--Congresses.
Balkan Peninsula--History--Congresses.
Borderlands--Europe--History--Congresses.
Europe--Relations--Turkey--Congresses.
Turkey--History--Ottoman Empire, 1288-1918--Congresses.
Turkey--Relations--Europe--Congresses.
Princeton subject headings:
Austria--History--Congresses.
Balkan Peninsula--History--Congresses.
Borderlands--Europe--History--Congresses.
Europe--Relations--Turkey--Congresses.
Turkey--History--Ottoman Empire, 1288-1918--Congresses.
Turkey--Relations--Europe--Congresses.