References
- Rowan, J. (1998). Explorations in the subtle. Transpersonal Psychology Review, 2(3), 32–42.
- Schutz, W. (1988). Profound simplicity (3rd ed.). Muir Beach: William Schutz Associates.
- Wilber, K. (1996). The eye of spirit. Boston, MA: Shambhala.
- Wilber, K. (2006). Integral spirituality. Boston, MA: Integral Books.