The digital library of the Russian Geographical Society, containing thousands of digitized books, maps, atlases, periodicals, expedition reports, and other types of materials of the Society.
Digital library developed by a group of Russian specialists. Here you can find tons of Soviet and contemporary books, journals, newspapers of all kinds, especially academic publications.
Digital library of the National Library of the Republic of Karelia, containing many digitized local publications of the Soviet period. It also has a lot of publications and manuscripts in Finnish language.
Digital library of the Russian Academy of Sciences that provides open access to extensive digitized academic publications as well as relevant archival documents, museum objects, and photographs.
Collection of digital open-access published materials from between 1917 and 1991 in the Russian State Library. In the link, the filter "otkrytii dostup" is already selected; if it is not, one should select it in order to view publicly available books.