Wertsch, James V. <br/><br/>
Voices of the mind :  a sociocultural approach to mediated action / 
James V. Wertsch. 
 - Cambridge, Mass. :  Harvard University Press,  1991. 
 - viii, 169 p. ;  24 cm. 
<br/><br/><label>ISBN: </label>0674943031  
<br/><br/><label>Dewey Class. No.: </label>150  / W499