Thick-billed Fox Sparrow - References

References

• Rising, Jim D. & Beadle, David (1996): A Guide to the Identification and Natural History of the Sparrows of the United States and Canada. Academic Press, San Diego.
• Sibley, David Allen (2000): The Sibley Guide to Birds. Alfred A. Knopf, New York.
• Swarth H. W. (1920): Revision of the avian genus Passerella with special reference to the distribution and migration of the races in California. University of California Publications in Zoology 21: 75–224.
• Weckstein, J. D.; Kroodsma, D. E. & Faucett, R. C. (2002): Fox Sparrow (Passerella iliaca). In: Poole, A. & Gill, F. (eds.): The Birds of North America 715. Academy of Natural Sciences, Philadelphia, PA & American Ornithologists' Union, Washington, D.C. Online version, retrieved 2006-11-27. (requires subscription)
• Zink, R. M. (1994): The Geography of Mitochondrial DNA Variation, Population Structure, hybridization, and Species Limits in the Fox Sparrow (Passerella iliaca). Evolution 48(1): 96-111. (HTML abstract, first page image)
• Zink, Robert M. & Kessen, A. E. (1999): Species Limits in the Fox Sparrow. Birding 31: 508-517.
• Zink, Robert M. & Weckstein, Jason D. (2003): Recent evolutionary history of the Fox Sparrows (Genus: Passerella). Auk 120(2): 522–527. HTML fulltext (without images)