Mathematical analysis; Functions, limits, series, continued fractions. (Matematicheskii analiz - funkt︠s︡ii, predeli, ri︠a︡dy, t︠s︡epnye droby) / 
Lyusternik, Lazar Aronovich.
Yanpolʹsky, Avraam Ruvimovich.
Spence, E.
Oxford, 
1965.