Moore, R. C., L. R. Cox, E. R. Trueman, N. D. Newell, and C. P. Nuttall. “Part N, Mollusca 6, Vol. 1, Ch. 1, P. 1–129”. Treatise on Invertebrate Paleontology (January 1, 1969). Accessed November 21, 2024. https://journals.ku.edu/InvertebratePaleo/article/view/5588.