Columbia subject headings:
Harvard subject headings:
Europe--History--476-1492.
Nicephorus II Phocas, Emperor of the East, 912-969.
Nicephorus II, Byzantine Emperor, 912 approximately-969.
Otto I, Holy Roman Emperor, 912-973.
Princeton subject headings:
Europe--History--476-1492--Sources.
Nicephorus II Phocas, Emperor of the East, 912-969.
Otto I, Holy Roman Emperor, 912-973.