Stridsberg, S. & Turek, V., 1997: A revision of the Silurian nautiloid genus Ophioceras Barrande. GFF, Vol. 119 (Pt. 1, March), pp. 21–36. Stockholm. ISSN1103-5897; Abstract.[2]
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Charles Hepworth Holland 2010. Coiled nautiloid cephalopods from the British Silurian. Proceedings of the Geologists’ Association 121 (2010) 13–23 [1]
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Stridsberg, S. & Turek, V., 1997: A revision of the Silurian nautiloid genus Ophioceras Barrande. GFF, Vol. 119 (Pt. 1, March), pp. 21–36. Stockholm. ISSN1103-5897; Abstract.[2]