Vilenkin, Naum Iakovlevich <br/><br/>
Combinatorics / 
by N. Ya. Vilenkin; translated from the Russian by A. Shenitzer and S. Shenitzer 
 - New York:  Academic Press,  1971 
 - xv,296 p. :  ill. ;  24 cm. 
<br/><br/> With answers 
<br/><br/><label>ISBN: </label>0127219404 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Combinatorial analysis