Columbia subject headings:
Daʻwah (Islam)
Ibadites--Doctrines.
Ibadites--Oman.
Oaths (Islamic law)
Harvard subject headings:
Daʻwah (Islam)
Ibadites--Doctrines.
Ibadites--Oman.
Princeton subject headings:
Ibadites.
Oaths (Islamic law)