Vaidya , Narendra <br/><br/>
How children discover knowledge  : theoritical and practical foudations of students investigations in science. 
Narendra Vaidya 
 - New Delhi  Oxford & IBH Publishing   c 1974 
 - xv ,315p.;    22cm 
<br/><br/><label>Dewey Class. No.: </label>370.13  /   VAI