Christian, Robert R. <br/><br/>
Introduction to logic and sets / 
by Robert R. Christian. 
 - 2d ed. 
 - Waltham, Mass. :  Blaisdell Pub.,  1965. 
 - xii, 116 p. :  ill., ;  21 cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Set theory.<br/>Logic, Symbolic and mathematical.