Otchet o Di︠e︡i︠a︡telʹnosti Nikolaevskoĭ Glavnoĭ fizicheskoĭ Observatorīi i podvi︠e︡domstvennykh eĭ uchrezhdenīĭ za 1910 god.
Central Physical Observatory (Leningrad)
S.-Peterburg,
1911.