Mason, Robert D. <br/><br/>
Programmed Leraning aid for Business and Economic Statistics. 

 - 3rd Ed. 
 - Ontario :  Learning Systems Company,  1978. 
 - xi, 156 p. 
<br/><br/><label>ISBN: </label>0256001197 
<br/><br/><label>Dewey Class. No.: </label>519  / MAS