1. Andreson, J., (2003) ‘Mysticism,’ in Encyclopedia of Science and Religion, NY: Macmillan. https://archive.org/stream/EncyclopediaOfScienceAndReligion/Encyclopedia%20of%20Science%20and%20Religion_djvu.txt Accessed July 22, 2017.
2. Clark, J. and Skinner, J.V., (1963) Meister Eckhart: Selected Treatises and Sermons, London, UK: Fontana Library of Theology and Philosophy.
3. Eckhart, M. (1981) The Sermons of Meister Eckhart, Mahwah, NJ: Paulist Press.
4. Freeman, J., (2014) “Seven Levels of Consciousness,” Development of Consciousness as Outlined by Maharishi, http://tmhome.com/books-videos/7-states-of-consciousness-video-interview/ posted Nov. 2014.
5. Forman, R.K.C., ed. (1990) The Problem of Pure Consciousness, NY: Oxford University Press