Thomas, Joseph Miller <br/><br/>
The four color theorem 

 - Durham, North Carolina :   1969. 
 - 10p.  : ill.   ; 26cm.  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Four color problems
<br/><br/><label>LC Class. No.: </label>PAM QA166.T5