Bjerreskov, M. “Upper Llandovery and Wenlock Cyrtograptus from the Silurian Peary Land Group, North Greenland”. Bulletin Grønlands Geologiske Undersøgelse 163 (January 1, 1992): 1–31. Accessed May 18, 2024. https://geusjournals.org/index.php/bullggu/article/view/6719.