Bleho, Barbara, Kevin Ellison, Dorothy P. Hill, and Lorne K. Gould. 2015. “Chestnut-collared Longspur (Calcarius ornatus).” The Birds of North America, edited by Paul G. Rodewald. Ithaca: Cornell Lab of Ornithology. Retrieved from the Birds of North America: https://birdsna.org/Species-Account/bna/species/chclon doi: 10.2173/bna.288