372.21<br/>PIA<br/><br/>
5540<br/><br/>
Piaget, Jean <br/><br/>
THE CHILD'S CONCEPTION OF NUMBER 

. – LONDON :  ROUTLEDGE AND KEGAN PAUL LTD..
<br/><br/>ix, 248 p. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>CHILD EDUCATION
<br/><br/><label>Dewey Class. No.: </label>372.21  / PIA