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Crônier, Catherine; Feist, Raimond (2000). "Evolution et systématique du groupe Cryphops (Phacopinae, Trilobita) du Dévonien Supérieur" [Evolution and systematics of the Cryphops group (Phacopinae, Trilobita) from the Late Devonian]. Senckenbergiana Lethaea. 79 (2): 501–515. doi:10.1007/bf03043651. S2CID131283519.
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Crônier, Catherine; Feist, Raimond (2000). "Evolution et systématique du groupe Cryphops (Phacopinae, Trilobita) du Dévonien Supérieur" [Evolution and systematics of the Cryphops group (Phacopinae, Trilobita) from the Late Devonian]. Senckenbergiana Lethaea. 79 (2): 501–515. doi:10.1007/bf03043651. S2CID131283519.