1. Dewey, C. P. 1987. Paleoecology of a hypersaline Carboniferous ostracod fauna. J. micropalaeontol., London, 6 (2), 29–33.
2. Dewey, C. P. 1988. Lower Carboniferous ostracode assemblages from Nova Scotia. In Hanai,T, Ikeya, N. & Ishizaki, K. (Eds), Evolutionary biology of Ostracoda, its fundamentals and applications, proceedings of the Ninth International Symposium on Ostracoda, held in Shizuoka, Japan, 29 July–2 August 1985, Developments in palaeontology and stratigraphy, 11, 685–696. Kodansha Ltd., Tokyo and Elsevier, Amsterdam, Oxford, New York, Tokyo.
3. Fisher, W. L. 1980. Variation in stratigraphy and petrology of the uppermost Hamlin Shale and Americus Limestone related to the Nemaha structural trend in northeastern Kansas. Unpub. doctoral dissertation, The University of Kansas, Lawrence, Kansas. 166 pp.
4. Geinitz, H. B. 1866 (1867). Carbonformation und Dyas in Nebraska. Verhandlungen der Kaiserlichen Leopoldino-Carolinischen deutschen Akademie der Naturforscher, Dresden, 91 pp.
5. Harbaugh, J. W. & Demirmen, F. 1964. Application of factor analysis to petrologic variations of Americus Limestone (Lower Permian), Kansas and Oklahoma. Kans. State Geol. Surv. Spec. Distrib. Publ., Lawrence, Kasas, 15, 1–40.