Alexandroff, Paul. <br/><br/>
Elementary concepts of topology / 
Paul Alexandroff, with a preface by David Hilbert, translated by Alan E. Farley. 
 - New York :  Dover Publications,  c1961. 
 - 63 p. :  ill. 
<br/><br/> Translation of: Einfachste grundbegriffe der topologie. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Topology.