PEEL, J. Ceratopea billingsi (Gastropoda) from the Early Ordovician of Kronprins Christian Land, eastern North Greenland. Rapport Grønlands Geologiske Undersøgelse, Copenhagen, Denmark, v. 101, p. 68–68, 1980. DOI: 10.34194/rapggu.v101.7723. Disponível em: https://geusjournals.org/index.php/rapggu/article/view/7723. Acesso em: 3 jul. 2024.