Dokembriĭ i paleozoĭ Sibiri i smezhnykh regionov : paleontologi︠i︡a, biostratigrafi︠i︡a, paleobiogeografi︠i︡a : sbornik nauchnykh trudov - Sokolov, Boris Sergeevich, 1914-; Elkin, Evgeniĭ Aleksandrovich (Institut, 1976)