Nicholson, Reynold Alleyne
Studies in Islamic mysticism
University Press , 1967
 Buku Teks
Al-Attas, Syed Muhammad Naguib
Mysticism of Hamzah Fansuri
Kuala Lumpur : University of Malay Press, 1970.
 Buku Teks
Collins, John Edward
Mysticism and new paradigm psychology
Rowman & Littlefield, 1991
 Buku Teks
Khan, Hazrat Inayat
Philosophy, Psychology, Mysticism
The Sufi International Headquarter's, 1956
 Buku Teks
Suzuki, Daisetz Teitaro, 1870-1966
Mysticism : Christian and Buddhist
Harper, 1957
 Buku Teks