Lewis, Clarence Irwing, 1883- <br/><br/>
Symbolic logic / 
Clarence Irving Lewis and Cooper Harold Langford 
 - 2nd ed. 
 - New York:  Dover Pub. Inc.,  1959 
 - 518 p. ;  21 cm. 
<br/><br/><label>LCCN: </label>59-4164 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Logic, Symbolic and mathematical