Waud,Roger N. <br/><br/>
Microeconomics / 
Roger N. Waud 
 - 4ta ed. 
 - New york :  Harper & Row,  1989       
 - 454 p. 
<br/><br/><label>ISBN: </label>0060469382 
<br/><br/><label>LC Class. No.: </label>HB 172 W354m 1989