Merriam, D. F., W.R. Atkinson, Paul C. Franks, Norman D. Plummer, and F.W. Preston. “Description of a Dakota (Cretaceous) Core from Cheyenne County, Kansas”. Bulletin (Kansas Geological Survey), no. 134 (January 1, 1958): 1–104. Accessed January 3, 2026. https://journals.ku.edu/kgsbulletin/article/view/20566.