Balyshev M. Ludwig O. Struve (1858-1920): The beginning of positional astronomy in the Kharkiv Astronomical Observatory. Ukrainian. 2021 ;37(5):74-82.

¹Vavilova IB, ¹Artemenko TG, ¹Pakuliak LK. Database "Astronomers - Ukraine" in the UkrVO portal. Russian. 2014 ;30(1):70-.

¹Balyshev MA. Historical and biographical research of life and scientific activity of Boris Semeykin (1900-1938). Ukrainian. 2018 ;34(2):71-75.

¹Korsun AA. Determination of secular polar motion from astronomical observations. The priority of O. Ya. Orlov. 2016 ;32(2):74-80.