Thorndike, E. L., Bregman, E. O., Tilton, J. W., & Woodyard, E. (1928). Adult learning. Macmillan Co..

Thorndike, Edward L., Elsie Oschrin Bregman, John Warren Tilton, and Ella Woodyard. Adult Learning. New York: Macmillan Co., 1928.

Thorndike, Edward L., et al. Adult Learning. Macmillan Co., 1928.