Klapper, Gilbert. “Patrognathus and Siphonodella (Conodonta) from the Kinderhookian (Lower Mississippian) of Western Kansas and Southwestern Nebraska”. Bulletin (Kansas Geological Survey), no. 202 (January 1, 1971): 1–14. Accessed December 30, 2025. https://journals.ku.edu/kgsbulletin/article/view/22285.