Jeffrey, Richard. <br/><br/>
Formal logic: ITs scope and limits /  

 - second edn. /  
 - New YOrk :   McGraw-Hill Book Company ,   1970 
 - xiv,198p ;  
<br/><br/><label>ISBN: </label>0 -07-032321-6 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Philosophy<Soundness>
<br/><br/><label>Dewey Class. No.: </label>R1  / M9