Columbia subject headings:
Balkan Peninsula--Foreign relations--20th century.
Balkan Peninsula--Politics and government--20th century.
Eastern question (Balkan)
Europe--Politics and government--1871-1918.
Harvard subject headings:
Balkan Peninsula--Foreign relations--20th century.
Balkan Peninsula--Politics and government--20th century.
Eastern question (Balkan)
Europe--Politics and government--1871-1918.
Princeton subject headings:
Balkan Peninsula--Foreign relations--20th century.
Balkan Peninsula--Politics and government--20th century.
Eastern question (Balkan)
Europe--Politics and government--1871-1918.