Русская Правда
His major works include "A Study of Russkaya Pravda" (1941), "Old Russian Cities" (1956, 2nd ed.), "Medieval Moscow" (1957), "Russia in the Sixteenth Century" (1962), "Russian Culture from the Tenth to the Eighteenth Century" (1968), "The Russian State from the Fourteenth to the Seventeenth Century" (1973), and "Ancient Rus" (1975).