Malyarchuk said the Mongoloid component of Slavic people was partially added before the split of "Balto-Slavics" in what time period?
Malyarchuk said that other Slavs "Mongoloid component" was increased during the waves of migration from "steppe populations (Huns, Avars, Bulgars and Mongols)", especially the decay of the "Avar Khaganate".