Hypatian Codex
An alternative version of Russian origin was presented by another Russian historian, Maksim Yemelyanov-Lukyanchikov. He believes that Zachary Chet was an ancient boyar clan that served Daniel of Galicia and appeared in Kostroma at the end of the 13th century. Presumably he was the one who brought the Hypatian Codex, which later was found in the Hypatian Monastery.