Columbia subject headings:
Ertuğrul Gazi, 1198-1288.
Seljuks--Turkey--Biography.
Turkey--History--To 1453.
Harvard subject headings:
Ertuğrul Gazi, 1198-1288.
Seljuks--Turkey--Biography.
Turkey--History--To 1453.
Princeton subject headings:
Ertuğrul Gazi, 1198-1288.
Seljuks--Turkey--Biography.
Turkey--History--To 1453.