Columbia subject headings:
Ibadites--Doctrines--Congresses.
Ibadites--History--Congresses.
Islam--Doctrines--Congresses.
Islamic sects--Congresses.
Harvard subject headings:
Ibadites--Doctrines--Congresses.
Ibadites--History--Congresses.
Islam and state--Congresses.
Islam--History--Congresses.
Islam--Theology--Congresses.
Princeton subject headings:
Ibadites--Doctrines--Early works to 1800.
Ibadites--Early works to 1800.