Mineraly rudnykh mestorozhdeniĭ i pegmatitov Urala - Igumnov, A. N.; Cherv︠i︡akovskiĭ, Gennadiĭ Fomich (Trudy Instituta geologii (Institut geologii (Akademi︠i︡a nauk SSSR. Uralʹskiĭ filial)) ;, 1965)