Columbia subject headings:
ʻUthmān ibn ʻAffān, Caliph, -656.
Harvard subject headings:
Islamic Empire--Kings and rulers.
Islamic Empire--Politics and government.
ʻUthmān ibn ʻAffān, Caliph, -656.
Princeton subject headings:
ʻUthmān ibn ʻAffān, Caliph, -656.