Hansen, Jesper, and Lars E. Holmer. “Taxonomy and Biostratigraphy of Ordovician Brachiopods from Northeastern Ny Friesland, Spitsbergen”. Zootaxa 3076, no. 1 (October 28, 2011): 1–122. Accessed May 22, 2025. https://mapress.com/zt/article/view/zootaxa.3076.1.1.