The Ordovician zone index conodont Amorphognathus ordovicicus Branson & Mehl, 1933 from its type locality and the evolution of the genus Amorphognathus Branson & Mehl, 1933. Stig M. Bergström and Stephen A. Leslie, April 2010, Journal of Micropalaeontology, 29, pages 73-80, doi:10.1144/jm.29.1.73
