REFERENCES
- Erikson, Erik H.: Childhood and society. New York: W. W. Norton & Co., Inc., 1950.
- Kanner, Leo: Child Psychiatry. Springfield, III.: Charles C Thomas, 1935.
- Mitchell, E. D. & Mason, B. S.: The Theory of Play. New York: A. S. Bames & Co., Inc., 1935.
- Waelder, Robert: The Psychoanalytic Theory of Play. This quarterly, II, 1933.