Rasmussen, Jan Audun, Mats E. Eriksson, and Anders Lindskog. 2021. “Middle Ordovician Drepanoistodus (Vertebrata, Conodonta) from Baltica, With Description of Three New Species”. European Journal of Taxonomy 774 (1):106–134. https://doi.org/10.5852/ejt.2021.774.1533.