Olsson, William. <br/><br/>
Stockhokm: its structure and developement. 

 - New York-US :   Geografical record,   1940. 
 - páginas 420-438 :   Ilustraciones blanco y negro 
 - Irregular 
 - Vol. XXX, no. 3(Jul. 1940) 
 - The Geographical Review ;   no. 3 .
 - The Geographical Review. .