Columbia subject headings:
Islamic Empire--History--661-750.
Muʻāwiyah ibn Abī Sufyān, Caliph, -680.
Harvard subject headings:
Princeton subject headings:
Islamic Empire--History--622-661--Early works to 1800.
ʻAlī ibn Abī Ṭālib, Caliph, approximately 600-661--Campaigns--Early works to 1800.