古代エジプト人の魂
———. 2001. "Akh". In The Oxford Encyclopedia of Ancient Egypt, edited by Donald Bruce Redford. Vol. 1 of 3 vols. Oxford, New York, and Cairo: Oxford University Press and The American University in Cairo Press. 47–48.
Jaynes, Julian. 1976. The Origin of Consciousness in the Breakdown of the Bicameral Mind, Princeton University.
Žabkar, Louis Vico. 1968. A Study of the Ba Concept in Ancient Egyptian Texts. Studies in Ancient Oriental Civilization 34. Chicago: University of Chicago Press