His magnum opus, "Explanatory Dictionary of the Living Great Russian Language", was published in four huge volumes in 1863–1866. "The Sayings and Bywords of the Russian people", featuring more than 30,000 entries, followed several years later. Both books have been reprinted innumerable number of times. Baer says: "While an excellent collector, Dal had some difficulty ordering his material, and his so-called alphabet-nest system was not completely satisfactory until Baudouin de Courtenay revised it thoroughly in the third (1903–1910) and fourth (1912–1914) editions of the "Dictionary"."