Cox, L. R., T. Soot-Ryen, C. C. Brasnson, H. B. Stenzel, Aurèle LaRocque, A. Myra Keen, H. S. Puri, et al. “Part N, Mollusca 6, Vol. 2, Ch. 6, P. 690–868”. Treatise on Invertebrate Paleontology (January 1, 1969). Accessed October 4, 2024. https://journals.ku.edu/InvertebratePaleo/article/view/5593.