Sivov 1957. Cambrian System Stratigraphical sketch Atlas of the leading forms of the fossil fauna and flora of Western Siberia I., L. L. Khalfin [ed.], Atlas of the leading forms of the fossil fauna and flora of Western Siberia I. Moscow 1955 : 58-74 text-figs. 114-116 table 1. [In Russian.]", 1957: 58-74. Chapter pagination: 58-74