TY JOUR TI Calcite in the shells of Silurian brachiopods of the Pentamerida order KW brachiopods KW Silurian KW calcite KW microstructure JO Proceedings of the Komi Science Centre of the Ural Division of the Russian Academy of Sciences AU Katkova, V.I. AU Beznosova, T.M. PY 2026 IS 0 PB FSBI FIC "Komi Scientific Center of the Ural Branch of the Russian Academy of Sciences"