12Dickinson, Edward C., ed. (2003) , The Howard and Moore Complete Checklist of the Birds of the World, 3rd edition
12American Ornithologists' Union (2000) Forty-second supplement to the American Ornithologists' Union check-list of North American birds, The Auk, vol. 117, no. 3
↑Lee, Sang-im, Cynthia S. Parr, Youna Hwang, David P. Mindell, and Jae C. Choe (2003) Phylogeny of magpies (genus Pica) inferred from mtDNA data, Molecular Phylogenetics and Evolution, vol. 29, no. 2
↑Clements, James F. (2007) , The Clements Checklist of Birds of the World, Sixth Edition
