Programmed learning aid for basic principles of the social sciences / 
 Basic principles of the social sciences. 
Paul B. Horton... [et al.] 
 - Homewood, Illinois :  Learning Systems Co.,  1973. 
 - 189 p. ;  25 cm. 
<br/><br/><label>ISBN: </label>0256014744 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Social sciences.