Brualdi, Richard A. <br/><br/>
Introductory combinatorics / 
Brualdi, Richard A. 
 - 4th ed. 
 - New Delhi:  Pearson Education,  2008. 
 - ix, 630p.; 24cm. 
<br/><br/>Includes bibliographical references. 
<br/><br/><label>ISBN: </label>9788131718827 
<br/><br/><label>Dewey Class. No.: </label>511.6 BRU