Columbia subject headings:
Europe--Foreign relations--1871-1918.
Europe--History--July Crisis, 1914.
World War, 1914-1918--Causes.
Harvard subject headings:
Europe--Foreign relations--1871-1918.
Europe--History--July Crisis, 1914.
World War, 1914-1918--Causes
Princeton subject headings:
Europe--Foreign relations--1871-1918.
Europe--History--July Crisis, 1914.
World War, 1914-1918--Causes.