1. Catania, A. C. (1998). Learning (4th ed.). Upper Saddle River, NJ: Prentice-Hall.
2. Catania, A. C. & Keller, K. J. (1981). Contingency, contiguity, correlation, and the concept of causation. In P. Harzem & M. D. Zeiler (Eds.), Predictability, correlation, and contiguity. Advances in analysis of behaviour, volume 2 (pp. 125–167). Chichester: Wiley.
3. Ferster, C. B. & Skinner, B. F. (1957). Schedules of reinforcement. New York: Appleton-Century-Crofts.