Sufism
Some of the major, notable Sufis in history, from the 'classical age' of Sufism,  include:<ref>The classical reference volume which gives the biographies of most of the great early Sufi saints is Sheikh Farid-ud-din Attar's, Tazkirat al-Aulia'''' (A Mention/Remembrance of the Saints), English translation by Prof AJ Arberry, n.d.; the online version is available at http://www.maktabah.org/biography/sufi-saints/392-tazkirat-al-aulia-by-fariduddin-attar.html, Maktabah Islamic E-Librray site, Retrieved 2.10.2012</ref>