Centro Vasco de Arquitectura
Euskal Herriko Arkitektura Ikerkundea
CURTIS William. J. La arquitectura moderna desde 1900. Edit. Phaidon. Hong Kong, 2006. 3ª edición en español. 1ª edición 1986 (edición original 1982)
http://dcaiga.blogspot.com.es/2011/07/national-farmers-bank-of-owatonna.html
http://archpaper.com/news/articles.asp?id=5061
http://www.mnopedia.org/multimedia/national-farmers-bank-owatonna
http://www.flickriver.com/photos/switzers_nursery/8109400238/
http://travelphotobase.com/v/USMN/MNT032.HTM
http://www.flickriver.com/photos/switzers_nursery/8109399467/
http://www.greatbuildings.com/buildings/National_Farmers_Bank.html
http://www.oberlin.edu/images/Art240/Art240.html
http://www.mnpreservation.org/2011/03/02/little-bus-on-the-prairie/
http://www.flickriver.com/photos/tags/nationalfarmersbank/interesting/
http://louis-sullivan.blogspot.com.es/
http://en.wikipedia.org/wiki/File:LSOwatannaBank2.jpg
http://louis-sullivan.blogspot.com.es/2011/06/louis-sullivan-obras-parte-ii.html
http://www.greatbuildings.com/cgi-bin/gbi.cgi/National_Farmers_Bank.html/cid_aj1937_b.html