Herman, J.S.; Van Waes, H (1993). Elasmobranches et stratigraphie. Professional Paper. Geological Survey of Belgium, 1993/06(264). Geologische Dienst van België: Brussel. 260 pp., 55 figs., 42 p pp.
Part of: Professional Paper. Geological Survey of Belgium. Belgische Geologische Dienst: Brussel. ISSN 0378-0902, more