Authors Year Title
Bisat 1950 The junction faunas of the Viséan and Namurian.
Transactions of the Leeds Geologists Association., 6 (3): 10-26, fig.1, pl.1,2; Kendal.
Ruzhencev & Bogoslovskaya 1971a Namiurskii etap v evoliutsii ammonodei. Rannenamiurskie ammonoidei.
Trudy Paleontologicheskogo Instituta Akademiya Nauk SSSR, 133: 1-382, fig.1-89, pl.1-40; Moskva.