The papers of Mark Aleksandrovich Landau consist of correspondence (over 200 letters and over 40 postcards) to Ivan A. Bunin (1870-1953), the Russian novelist and Nobel Prize winner, 1933, between 1921 and 1953. There are also over 100 letters and postcards from Landau and his wife to Mrs. I. A. Bunin, 1921-1957; letters to Vera Bunin, 1930-1948; letters to Vera Bunin, 1932-1955, with telegrams, cards and photo; and, letters 1948-1952.