Zeller, Doris E., and Thomas L. Thompson. “Age and Structure of Subsurface Beds in Cherokee County, Kansas - Implications from Endothyrid Foraminifera and Conodonts”. Bulletin (Kansas Geological Survey), no. 211 (January 1, 1977): 1–11. Accessed January 3, 2026. https://journals.ku.edu/kgsbulletin/article/view/22259.