Authors Year Title
Kullmann, Wagner & Winkler_Prins 2007 Significance for international correlation of the Perapertú Formation in Northern Palencia, Cantabrian Mountains. Tectonic/stratigraphic context and description of Mississippian and Upper Bashkirian Goniatites.
Revista Española de Paleontología, 22 (2), 127-145, 8 fig.,  Madrid.
Librovitch 1941 Otryad Ammonoidea. In: Atlas rukovodyashchikh form iskopaemykh faun SSSR, t. IV. Nizhniy otdel kamennougol'noy sistemy.
Gosgeolizdat: 137-153, fig.13-43, pl.34-40; Moskva-Leningrad.
Nikolaeva, Kulagina & Pazukhin 2009 Paleontology and Microfacies of the Serpukhovian in the Verkhnyaya Kardailovka Section, South Urals, Russia: potential candidate for the GSSP for the Viséan-Serpukhovian boundary.(S.V.Nikolaeva, et al., for full authors see Note.
Newsletters on Stratigrahy, 43/2: 165-193, 8 fig.,3 pl., Berlin, Stuttgart.
Pitinova 1974 Stratigrafiya i ammonoidei Namyura Tsentral'nykh Kyzylkumov i Yuzhnoi Fergany.
1-66, 8 figs.,1 tab., 12 pls., Tashkent (Izdatel'stvo FAN Uzbekskoy SSR).
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.
Yang 1978 [On the Lower and Middle Carboniferous Subdivisions and Ammonoids of Western Guizhou.] [In Chinese.]
Professional Papers of Stratigraphy and Palaeontology, 5: 143-200, pl.40-46, Peking (Geological Publishing House).