Novyye vidy mollyuskov Crassiana praecrassoides i Potomida baschkirica iz akchagylskikh otlozheniy doliny r. Karmasan [New species of mollusks, Crassiana praecrassoides and Potomida baschkirica, from the Akchagylian deposits of the valley of the river Karmasan] - Sidnev, A.V. (1976)
in Russian; whole book at: https://www.geokniga.org/books/21702