Wilson, Robin J. <br/><br/>
Four colors suffice:  how the map problem was solved/ 
 Four colours suffice 
Robin Wilson. 
 - Princeton, N.J.:  Princeton University Press,  2002. 
 - xii, 262 p.:  ill., maps, ports.;  21 cm. 
<br/><br/> First published 2002 by Penguin Group, London. 
<br/><br/>Includes bibliographical references and index. 
<br/><br/><label>ISBN: </label>0691115338 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Mathematical recreations.<br/>Four-color problem.<br/>Four-color problem---History.
<br/><br/><label>Dewey Class. No.: </label>510.9  / W752f