Deregowski, Jan B. <br/><br/>
Perception of the two-pronged trident by two and three-dimensional p erceivers /    
Jan B. Deregowski. 
 - Lusaka :   Human Development Research Unit ,   1969. 
 - 9 p. :    diagrs. 
 - H. D. R. U. reports;   11 .
<br/><br/><label>Subjects--Topical Terms: </label><br/>Educational psychology--------