Olson, Everett C.; Beerbower, James R. (1953). "The San Angelo Formation, Permian of Texas, and Its Vertebrates". The Journal of Geology. 61 (5): 389–423. doi:10.1086/626109. ISSN0022-1376.
Olson, Everett C. (1962). "Late Permian terrestrial vertebrates, USA and USSR". Transactions of the American Philosophical Society. 52 (2): 1–224. doi:10.2307/1005904. ISSN0065-9746. JSTOR1005904.
Sidor, C.A. & Hopson, J.A. (1995). "The taxonomic status of the Upper Permian eotheriodont therapsids of the San Angelo Formation (Guadalupian), Texas". Journal of Vertebrate Paleontology. 15 (suppl. 3): 53A. doi:10.1080/02724634.1995.10011277.
Milner, Andrew R.; Sequeira, Sandra E. K. (2004-06-11). "Slaugenhopia texensis(Amphibia: Temnospondyli) from the Permian of Texas is a primitive tupilakosaurid". Journal of Vertebrate Paleontology. 24 (2): 320–325. doi:10.1671/1974. ISSN0272-4634.
Olson, Everett C. (1962). "Late Permian terrestrial vertebrates, USA and USSR". Transactions of the American Philosophical Society. 52 (2): 1–224. doi:10.2307/1005904. ISSN0065-9746. JSTOR1005904.
Olson, Everett C.; Beerbower, James R. (1953). "The San Angelo Formation, Permian of Texas, and Its Vertebrates". The Journal of Geology. 61 (5): 389–423. doi:10.1086/626109. ISSN0022-1376.
Olson, Everett C. (1962). "Late Permian terrestrial vertebrates, USA and USSR". Transactions of the American Philosophical Society. 52 (2): 1–224. doi:10.2307/1005904. ISSN0065-9746. JSTOR1005904.
Milner, Andrew R.; Sequeira, Sandra E. K. (2004-06-11). "Slaugenhopia texensis(Amphibia: Temnospondyli) from the Permian of Texas is a primitive tupilakosaurid". Journal of Vertebrate Paleontology. 24 (2): 320–325. doi:10.1671/1974. ISSN0272-4634.