Novgorodsko-Sofiysky Svod
According to Russian philologist Aleksey Shakhmatov, Novgorodsko-Sofiysky Svod is a tentative name for a hypothetical common source for the Novgorod Fourth Chronicle and the Sofia First Chronicle.
Shakhmatov initially dated it by 1448, but later revised his opinion to 1430s. Some Russian philologists shared his opinion, while others attribute the common source to the 1418 compilation of Photius, Metropolitan of Moscow.
