Columbia subject headings:
Caliphate--History.
Turkey--History--Ottoman Empire, 1288-1918.
Turkey--Social conditions--1288-1918.
Harvard subject headings:
Caliphate--History
Turkey--History--Ottoman Empire, 1288-1918.
Turkey--Social conditions--1288-1918.
Princeton subject headings:
Caliphate--History.
Turkey--History--Ottoman Empire, 1288-1918.
Turkey--Social conditions--1288-1918.