Chellas, Brian F. <br/><br/>
Modal logic :  an introduction / 
Brian F. Chellas. 
 - Cambridge [Eng.] ;  New York :  Cambridge University Press,  [1980] 
 - xii, 295 p. :  ill. ;  24 cm. 
<br/><br/> Includes indexes. 
<br/><br/>Bibliography: p. [278]-279. 
<br/><br/><label>ISBN: </label>0521224764 0521295157 (pbk.) 
<br/><br/><label>LCCN: </label>76047197 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Modality (Logic)