Principles of Microeconomics  
Ruffin Roy . 
 - 7th ed. 
 - London:  Addison Wesley ,  2001. 
 - xxxi,792 p.; 
<br/><br/><label>ISBN: </label>0321077318 
<br/><br/><label>LC Class. No.: </label>HB172  / .R83 2001