Neuschwander, Cindy. <br/><br/>
Sir Cumference and the Viking's map  a math adventure 
Cindy Neuschwander 
 - ed. 
 - [S.l.]  Charlesbridge  2012 
 - 32 p. 
<br/><br/><label>ISBN: </label>9780329919764 (Follett bdg.) 9781570917912 (trade) 9781570917929 (pbk.)