"Merttens,Ruth" <br/><br/>
Abacus Evolve Textbook 3 (6) 

 - uk  ,Pearson Education  2011 
 - 80 
<br/><br/><label>ISBN: </label>9789060257588 
<br/><br/><label>Dewey Class. No.: </label>510  / t-1309