Keller, Fred Simmons,  1899- <br/><br/>
Learning :  reinforcement theory / 
Fred S. Keller. 
 - 2nd ed. 
 - New York :  Random House,  1969. 
 - 82 p. :  ill. ;  19 cm. 
 - Random house studies in psychology .
<br/><br/><label>Subjects--Topical Terms: </label><br/>Learning, Psychology of.