00715cam a22002052 4500 mic58006366 DLC 20260227111612.0 940505s1957 xx a a 000 0 eng mic58006366 DLC DLC DLC Microfilm 5415 BF Baer, Donald M. (Donald Merle), 1931-2002. The reinforcing character of stimuli discriminative for early caretaking in kittens. [n.p., n.d.] 39 l. illus. Thesis--University of Chicago. Microfilm. Chicago [Library, Dept. of Photographic Reproduction, University of Chicago] 1957. Reinforcement (Psychology) [from old catalog] 39102 39102