Berenbaum, Michael, Skolnik, Fred (2006). Encyclopedia Judaica, Second Edition, volume 3, Urim Publications.
Dilts, Robert (2003). From Coach to Awakener, Meta Publications.
Eisenberg, Yehuda (1981). "Sensation and Emotion in the Obligations of Hearts," Da'at 7, pp. 5-35.
Hospers, John(1957). An introduction to philosophical analysis, London, Routledge.
Ilan, Nahem (2005). Al-I'tidal al-Shari'i: Another Examination of the Perception of Asceticism in The Duties of the Heart of Bahya, Jerusalem, Lander Institute.
Langer, Susanne K(1967). An Introduction to Symbolic Logic, New York, Dover Publications.
Lobel, Diana(2007). A Sufi-Jewish Dialogue Philosophy and Mysticism in Bahya ibn Paquda's "Duties of the Heart", University of Pennsylvania Press.
Stillman, A, Norman(2010). Encyclopedia of Jews in the Islamic world, Vol 2, Brill.
Whitney, William Dwight(1896). The century dictionary and cyclopedia, a work of universal reference in all departments of knowledge with a new atlas of the world, New York, The Century co.
Ya'aqov Yosef of Polonnoy(1881). Toledot Ya'aqov Yosef, Parshat Bo, ed. Varsovie, fol. 51b and 52d, Cited by Paul Fenton, Paris, Verdier.