Columbia subject headings:
Caliphate.
Hadith--Authorities.
Imamate.
Islam and state.
Islamic Empire--History.
Harvard subject headings:
Caliphate--Early works to 1800.
Hadith--Authorities--Early works to 1800.
Imamate--Early works to 1800.
Islam and state--Early works to 1800.
Islamic Empire--Politics and government--Early works to 1800.
Princeton subject headings:
Caliphate.
Hadith--Authorities.
Imamate.
Islam and state.
Islamic Empire--History.