Sapelnikov & Mizens 1982. [Silurian atrypids from the eastern slope of the Urals.] Khodalevich, A.N.; Breivel, M.G.; Mizens, L.I.; Nikitin, I.F.; Nikiforova, O.I.; Sapelnikov, V.P.[Eds]. [New data on the systematics and morphogenesis of Early Palaeozoic brachiopods.], Acad. Sci. USSR, Urals Scientific Centre, Sverdlovsk, 1982: 1-64. Chapter pagination: 23-29