Serpell, Robert <br/><br/>
Discrimination of orientation by Zambian children /  
Robert Serpel l. 
 - Lusaka :    Human Development Research Unit ,    1968. 
 - 12 p. :    diagrs. 
 - H. D. R. U. reports;    7 .
<br/><br/><label>Subjects--Topical Terms: </label><br/> Learning ability<br/> Comprehension -- testing<br/> Perception