•Johnsgard, Paul A. North American Owls: Biology and
Natural History, 1997,
Smithsonian Institution.
•Konig, C. Weick, F. & Becking, J. Owls: A Guide to
Owls of the World, 1999, Pica
Press
•Field Guides – Sibley, Peterson, National
Geographic
•www.birds.cornell.edu/programs/AllAboutBirds/BirdGuide/Boreal_Owl_dtl.htm
•www.owling.com/Boreal_nh.htm
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