1. Herrigel E., Zen and the Art of Archery (London: Pantheon, 1953), p. 11.
2. Naranjo C., Ornstein R., On the Psychology of Meditation (New York: Viking, 1971; an Esalen book), p. 9.
3. Ornstein R. E., The Psychology of Consciousness (San Francisco: W. H. Freeman, 1972), pp. 156–157.