Gans, David,  1907- <br/><br/>
An introduction to non-Euclidean geometry/ 
David Gans. 
 - New York:  Academic Press,  [1973]. 
 - xii, 274 p.:  illus.,  24 cm. 
<br/><br/>Bibliography: p. 263. 
<br/><br/><label>ISBN: </label>0122748506 
<br/><br/><label>LCCN: </label>72009326 //r85 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Geometry, Non-Euclidean.
<br/><br/><label>Dewey Class. No.: </label>516.1  / G199i