http://bna.birds.cornell.edu/bna/

http://en.wikipedia.org/wiki/List_of_North_American_birds

http://en.wikipedia.org/wiki/Category:Birds_of_North_America

http://birdsnorthamerica.com/

http://www.dmoz.org/Recreation/Birding/North_America/

http://identify.whatbird.com/mwg/_/0/attrs.aspx

http://www.currentcatalog.com/086748.html

http://www.pronto.com/mpm/search-birds-of-north-america:-a-guide-to-field-identification/

http://www.adoremusbooks.com/birdsofnorthamerica.aspx

http://www.birds.cornell.edu/pr/RestoringBirdsJan2007Web.pdf

http://whatbird.wildbird.com/mwg/_/0/attrs.aspx