Referencias
Enciclopedia del mundo animal. Parragon, 2013. Pp. 74, 75.
W. Kress, Stephen. Hummingbird Gardens: Turning Your Yard Into Hummingbird Heaven. Brooklyn Botanic Garden, 2007.
Christiansen, Per. The encyclopedia of birds. Chartwell books, Inc., 2013. Pp. 42-45.
Greenewalt, Crawford H. Hummingbirds. Courier Corporation, 1960
Roth, Sally. Attracting Butterflies & Hummingbirds to Your Backyard: Watch Your Garden Come Alive With Beauty on the Wing. Rodale, 2002.
Williamson, Sheri. A Field Guide to Hummingbirds of North America. Houghton Mifflin Harcourt, 2001.
http://en.wikipedia.org/wiki/Hummingbird
http://animals.sandiegozoo.org/animals/hummingbird
http://www.dgif.virginia.gov/habitat/hummingbirds.asp
http://mdc.mo.gov/discover-nature/outdoor-recreation/backyard-bird-feeding/attracting-hummingbirds
http://animals.nationalgeographic.com/animals/birds/ruby-throat-hummingbird/