References
- Perls, F. S. (1947). Ego, hunger and aggression. London: Allen Unwin.
- Perls, F. S. (2012). From planned psychotherapy to Gestalt therapy: Essays and lectures, 1945–1965. Gouldsboro, Maine: Gestalt Journal Press.
- Perls, F. S., Hefferline, R., & Goodman, P. (1994/1951). (PHG). Gestalt therapy: Excitement and growth in the human personality. New York: Gestalt Journal Press (orig. 1951).