^Dunn, Jon L. and Alderfer, Jonathan (2011). National Geographic Guide to the Birds of North America. National Geographic Society. ISBN1426200722. CS1 maint: Multiple names: authors list (link)
^Simpson & Day (1999). A Field Guide to the Birds of Australia, 6th Edition. Penguin. ISBN0-691-04995-5.
This article is part of Project Glossary, an All Birds project that aims to write comprehensive articles on each term related to animals.