Tschuvashov 1980. [Fusulinids of the Parafusulina solidissima zone in the Urals.] Rauzer-Chernousova, D.M.; Chuvashov, B.I.[Eds]. Biostratigrafiya artinskogo i kungurskogo yarusov Urala. [Biostratigraphy of the Artinskian and Kungurian stages of the Urals.], Urals Science Centre, Sverdlovsk, 1980: 1-150. Chapter pagination: 56-71