Ruffin, Roy, <br/><br/>
Principles of economics 
Roy Ruffin, Paul Gregory. 
 - Glenview, Ill. :  Scott,Foresman and Company,  1983. 
 - xxxii, 798 pages :  illustration;  27cm. 
<br/><br/>Includes index 
<br/><br/><label>ISBN: </label>0673155080 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Economics