Talmudic Commentaries
Rabbi Krasilschikov authored a 20-volume dual-commentary on the Talmud Yerushalmi in Moscow between the years 1952-1965. However, this was done in secrecy, due to fear of and oppression by the Communist regime, which had outlawed the study of Torah. Violators of this ban were subject to severe punishment and exile to Siberia. The work of Rabbi Krasilschikov was done without the benefit of any formal academy, and with very few reference works. It is reported that he did not even have a complete set of Talmud Bavli.
Read more about this topic: Yitzchok Isaac Krasilschikov