Avraham Dovid Lavut. Beith Aharon VeHosafoth [concordance of the Bible, providing references to source material in Talmud, Midrash and seventy other works].

Author of the much vaunted Sha’ar HaKollel (1890), an invaluable appendix to the Siddur of R. Shneur Zalman of Liadi, the Chabad scholar R. Avraham Dovid Lavut served for forty years as rabbi of the Russian community of Nikolayev. A student of the Tzemach Tzedek and a maternal ancestor of the last Grand Rabbi of Lubavitch, Menachem Mendel Schneerson (II). See M.M. Laufer, Yemei Melech (1991) pp. 39-55. Lavut greatly expanded the original Beith Aharon (1690), broadening the scope of references to include works of Kabbalah and Chassidism, as well as adding additional notes to the Talmudim and Midrashim. Needless to say, when he finished enhancing it, it was not the same Books at all.