Weisstein, Eric W. <br/><br/>
CRC encyclopedia of mathematics, V.1, A-F   
by Eric W Weisstein 
 - 3rd ed. 
 - Boca Raton  CRC Press  2009 
 - 1-1472p 
<br/><br/><label>ISBN: </label>9781420072211 
<br/><br/><label>Dewey Class. No.: </label>510.3  / P09.1;1 'R'