Cox, L. R., T. Soot-Ryen, C. C. Brasnson, H. B. Stenzel, Aurèle LaRocque, A. Myra Keen, H. S. Puri, et al. 1969. “Part N, Mollusca 6, Vol. 1, Ch. 4, P. 393–489”. Treatise on Invertebrate Paleontology, January. https://doi.org/10.17161/dt.v0i0.5591.