Isaacs, Nathan,    1895-1966. <br/><br/>
New light on children's ideas of number,  
Nathan  Isaacs. 
 - [U.S. ed.] 
 - London :    Ward Lock Eduational Co. Ltd/    1960. 
 - 121 p. ;    22 cm. 
<br/><br/><label>Subjects--Personal Names: </label><br/> Piaget, Jean,   1896-1980. 
<br/><br/><label>Dewey Class. No.: </label>512.072 ISA