Henry E Kyburg <br/><br/>
Knowledge Representation and Defeasible Reasoning 

 - 
 -  Kluwer Academic  1990 
 - 423 
<br/><br/>  
<br/><br/><label>ISBN: </label>0-7923-0677-5 
<br/><br/><label>Dewey Class. No.: </label>004.8