BOARDMAN , Darwin R., II; WORK, David M.; MAPES, Royal H.; BARRICK, James E. Biostratigraphy of Middle and Late Pennsylvanian (Desmoinesian-Virgilian) ammonoids. Bulletin (Kansas Geological Survey), [S. l.], n. 232, p. 1–96, 1994. DOI: 10.17161/kgsbulletin.no.232.20477. Disponível em: https://journals.ku.edu/kgsbulletin/article/view/20477. Acesso em: 1 apr. 2025.