Columbia subject headings:
Caliphs--Biography.
Islamic Empire--History--622-661.
ʻAlī ibn Abī Ṭālib, Caliph, approximately 600-661.
Harvard subject headings:
Caliphs--Islamic Empire--Biography.
Islamic Empire--History--622-661.
Muḥammad, Prophet, -632--Travel.
Princeton subject headings:
Caliphs--Biography.
Islamic Empire--History--622-661.
ʻAlī ibn Abī Ṭālib, Caliph, approximately 600-661.