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Dyfyniad Arddull Chicago︠I︡Udovich, ︠I︡Akov Ėlʹevich. Regionalʹna︠i︡a Geokhimi︠i︡a Osadochnykh Tolshch. Leningrad: "Nauka," Leningradskoe otd-nie, 1981.
Dyfyniad MLA︠I︡Udovich, ︠I︡Akov Ėlʹevich. Regionalʹna︠i︡a Geokhimi︠i︡a Osadochnykh Tolshch. "Nauka," Leningradskoe otd-nie, 1981.
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