Vygotsky L S <br/><br/>
Collected works of L.S. Vygotsky  Vols.  3 - 6 

 - New York, USA  Plenum Press  1997 
 -  V.3 Problems of the theory and history of psychology .
<br/><br/><label>ISBN: </label>0-304-70521-7 
<br/><br/><label>Source: </label>Reference