Clark, David L., Klaus J. Miller, Stig M. Bergstrom, Willi Ziegler, Ronald L. Austin, Walter C. Sweet, Frank H. T. Rhodes, Anita G. Harris, and Maurits Lindstrom. “Part W, Miscellanea, Supplement 2, Complete Volume”. Treatise on Invertebrate Paleontology (January 1, 1981). Accessed May 4, 2024. https://journals.ku.edu/InvertebratePaleo/article/view/5665.