Olson, E.C. (1962). "Late Permian terrestrial vertebrates, USA and USSR". Transactions of the American Philosophical Society. 52 (2): 1–224. doi:10.2307/1005904.
Sidor, C.A.; Hopson, J.A. (1995). "The taxonomic status of the Upper Permian eutheriodont therapsids of the San Angelo Formation (Guadalupian), Texas". Journal of Vertebrate Paleontology. 15 (3 Suppl.): 53A. doi:10.1080/02724634.1995.10011277.
