LANGE, Walter H. <br/><br/>
Business and Consumer Marhematics 

 - 5th ed. 
 - Boston :  Irwin Publishers  1992 
 - xvi, 736p. 
<br/><br/><label>ISBN: </label>0-256-09135-8 
<br/><br/><label>Dewey Class. No.: </label>650.01513