Sommerville, Duncan M'Laren Young,  1879-1934. <br/><br/>
The elements of non-Euclidean geometry. 

 - New York:  Dover,  [1958]. 
 - 274 p.:  illus.,  18 cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Geometry, Non-Euclidean.
<br/><br/><label>Dewey Class. No.: </label>516.1  / S697e