Use of external representations in reasoning and problem solving :  analysis and improvement / 
edited by Lieven Verschaffel ... [et al.] 
 - London ;  Routledge,  2010. 
 - ix, 260 p. : 
<br/><br/><label>ISBN: </label>9780415556736 (hardback) 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Interaction analysis in education.
<br/><br/><label>Dewey Class. No.: </label>370.1524  / Us