Correspondence, diaries, documents, manuscripts, and printed materials. The collection consists chiefly of diaries, research materials, and his writings. Among the correspondents are: Mikhail Chekhov, Olga Chekhov, Roman Gul, Vladimir Ilin, Artur Luther, Sergei Melgunov, Bishop Serafim, Fedor Stepun, Ilia Surguchev, Alexandra Tolstoy, and Vladimir Zenzinov.