Cox, L. R., Ruth D. Turner, C. P. Nuttall, E. R. Trueman, D. W. Boyd, B. F. Perkins, H. S. Puri, et al. 1969. “Part N, Mollusca 6, Vol. 1 and 2, Complete Volume”. Treatise on Invertebrate Paleontology, January. https://doi.org/10.17161/dt.v0i0.5596.