NIELSEN, Arne Thorshøj. Palæozoikum. Varv, [S. l.], v. 1988, n. 2, p. 44–63, 1988. DOI: 10.7146/varv.v1988i2.144801. Disponível em: https://tidsskrift.dk/varv/article/view/144801. Acesso em: 6 dec. 2025.