1. Agras, W. S. Behavior modification: Principles and clinical applications. Boston: Little, Brown, 1972.
2. Aitchison, R. A. A low cost, rapid delivery point system with “automatic” recording. Journal of Applied Behavior Analysis, 1972, 5, 527–528.
3. Albee, G. W. Models, myths and manpower. Mental Hygiene, 1968, 52, 168–180.
4. Atthowe, J. M. Token economies come of age. Behavior Therapy, 1973, 4, 646–654.
5. Ayllon, T., & Azrin, N. H. The token economy. New York: Appleton-Century-Crofts, 1968.