• A. Akasoy, “What is Philosophical Sufism?” in P. Adamson (ed.), In the Age of Averroes (London: 2011), 229-49.

• W.C. Chittick, “Mysticism vs. Philosophy in Earlier Islamic History: the al-Ṭūsī, al-Qūnawī Correspondence,” Religious Studies 17 (1981), 87-104.

• W.C. Chittick, “Sadr al-Din al-Qūnawī on the Oneness of Being,” International Philosophical Quarterly 21 (1981), 171-84.

• W.C. Chittick, The Sufi Path of Love: the Spiritual Teachings of Rumi (Albany: 1983).

• W.C. Chittick, In Search of the Lost Heart: Explorations in Islamic Thought, ed. M. Rustom, A. Khalil and K. Murata (Albany: 2011).

• A. Schimmel, Mystical Dimensions of Islam (Chapel Hill: 1975).

• R. Todd, The Sufi Doctrine of Man: Ṣadr al-Dīn al-Qūnawī’s Metaphysical Anthropology (Leiden: 2014).