Wallis, W. D. <br/><br/>
Introduction to combinatorics 
by W D Wallis and J C George 
 - New York  CRC Press  2011 
 - xvi, 380p. 
 - Dicrete Mathematics and its Application   .
<br/><br/><label>ISBN: </label>9781439806227 
<br/><br/><label>Dewey Class. No.: </label>511.6  / P113 (CSA)