Romellen T. Gonzalvo and Romeo P. Conzalvo, Jr.  <br/><br/>
Contemporary Mathematics 

 -  Purely Books Trading & Publishing Corp.  2013 
<br/><br/> Includes References  
<br/><br/><label>ISBN: </label>978-971-95338-9-4 
<br/><br/><label>Dewey Class. No.: </label>Fil. 510 G58 2013