Razzell, Arthur G. <br/><br/>
Three and the shape of three / 
Arthur G. Razzell and K. G. O. Watts 
 - London :  Rupert Hart-Davis,  1964 
 - 32 p. :  ill. ;  26 cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Number concept<br/>Mathematical ability