Larry D. Martin; Evgeny N. Kurochkin; Tim T. Tokaryk (2012). "A new evolutionary lineage of diving birds from the Late Cretaceous of North America and Asia". Palaeoworld. 21: 59–63. doi:10.1016/j.palwor.2012.02.005.
Cracraft, Joel (1982). "Phylogenetic relationships and monophyly of loons, grebes, and hesperornithiform birds, with comments on the early history of birds". Systematic Zoology. 31 (1): 35–56. doi:10.2307/2413412. JSTOR2413412.
Stolpe, M. (1935). "Colymbus, Hesperornis, Podiceps: ein Vergleich ihrer hinteren Extremität". Journal für Ornithologie (in German). 83: 115–128. doi:10.1007/BF01908745. S2CID11147804.
Bell, A.; Chiappe, L. M. (2015). "A species-level phylogeny of the Cretaceous Hesperornithiformes (Aves: Ornithuromorpha): Implications for body size evolution amongst the earliest diving birds". Journal of Systematic Palaeontology. 14 (3): 239–251. doi:10.1080/14772019.2015.1036141. S2CID83686657.
Cracraft, Joel (1982). "Phylogenetic relationships and monophyly of loons, grebes, and hesperornithiform birds, with comments on the early history of birds". Systematic Zoology. 31 (1): 35–56. doi:10.2307/2413412. JSTOR2413412.
Stolpe, M. (1935). "Colymbus, Hesperornis, Podiceps: ein Vergleich ihrer hinteren Extremität". Journal für Ornithologie (in German). 83: 115–128. doi:10.1007/BF01908745. S2CID11147804.
Bell, A.; Chiappe, L. M. (2015). "A species-level phylogeny of the Cretaceous Hesperornithiformes (Aves: Ornithuromorpha): Implications for body size evolution amongst the earliest diving birds". Journal of Systematic Palaeontology. 14 (3): 239–251. doi:10.1080/14772019.2015.1036141. S2CID83686657.
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Holtz, Thomas R. Jr. (2012) Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages,Winter 2011 Appendix.