Arithmetic Teacher 29 

 - Philadelphia  NCTM  Mar. 1982 
 - 60 
 - 20091214 
 - Arithmetic Teacher  29 .
<br/><br/><label>ISSN: </label>1679-656X 
<br/><br/><label>Dewey Class. No.: </label>AMT 2009  / 2009