Assume areas in Central Asia with any sort of measurable Russian population speak Russian. Use the following maps to create a file in GeoJSON (or similar) format for use by pairmapper's languages-as-areas plugin: Kazakhstan_European_2012_Rus, Ethnicrussians1989ru, Lenguas_eslavas_orientales, NarodaCCCP. Try to cover all the areas where Russian is spoken at least as a major language.
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