context: 1 May] 1905 to a Russian-Ukrainian working-class family; he graduated from the St.
source: Tikhonov worked as an assistant engineer from 1924 to 1926.
reference_original: Тихонов работал помощником инженера с 1924 по 1926.
reference_flipped: Тихонова работала помощницей инженера с 1924 по 1926.