1. I.P. Pavlov, Conditioned Reflexes; An investigation of the Physiological Activity of the Cerebral Cortex, 1927 [G.V. Anrep, ed. tr.]
2. Nobel Lectures, Physiology or Medicine 1901–1921;Pavlov,1967
3. E. Thorndike, Animal Intelligence, 1911
4. Sur une forme particulière des réflexes conditionnels;Miller;C. R. Soc. Biol.,1928
5. Stevens' Handbook of Experimental Psychology, vol. III;Hall,2002