The nature of reinforcement 
edited by Robert Glaser. 
 - New York  Academic Press  1971. 
 - 379p. 24cm. 
<br/><br/> Includes bibliographical references and index  'A symposium of the Learning Research and Development Centre, University of Pittsburgh' 
<br/><br/><label>ISBN: </label>0122862504 
<br/><br/><label>LCCN: </label>78-171212 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Educational psychology