P. I. Usachev

• Sbornik posvi︠a︡shchennyĭ nauchnoĭ dei︠a︡telʹnosti pochetnogo chlena Akademii nauk SSSR, zasluzhennogo dei︠a︡teli︠a︡ nauki i tekhniki, Nikolai︠a︡ Mikhaĭlovicha Knipovicha (1885-1939)