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3. T. T. Efremova, Extended Abstract of Doctoral Dissertation in Biology (Novosibirsk, 1990).
4. T. T. Efremova, “Humus Status Parameters of Peat Soils,” Biol. Nauki, No. 10, 102–108 (1983).
5. T. T. Efremova, “Pedogenesis and the Diagnostics of Peat Soils in Bog Ecosystems,” Pochvovedenie, No. 12, 25–35 (1992).