Columbia subject headings:
Qurʼan--Criticism, interpretation, etc.--Early works to 1800.
Sufism--Doctrines--Early works to 1800.
Harvard subject headings:
Qurʼan--Criticism, interpretation, etc.--Early works to 1800.
Sufism--Doctrines--Early works to 1800.
Princeton subject headings:
Avicenna, 980-1037.