Georg Simmel. 

 - Englewood Cliffs, NJ :  Prentice-Hall,  [1965] 
 - Makers of modern social science .
<br/><br/>Bibliography : p. 180-182. Bibliographical footnotes. 
<br/><br/><label>Subjects--Personal Names: </label><br/>Simmel, Georg, 1858-1918. Simmel, Georg, 1858-1918.