1. P. S. Laplace, Traite de mecanique celeste (Duprat, Paris, 1799, 1802), Vols. 1, 2.
2. H. Poincaré, Sur les Courbes Definies par les Equations Differentielles: Oeuvres (Gauthier-Villars, Paris, 1951; Gostekhteoretizdat, Moscow, 1947).
3. N. D. Moiseev, Outlines of Stability Theory Development (GITTL, Moscow, 1949).
4. S. Lefschetz, Differential Equations: Geometric Theory (Interscience, New York, 1957; Inostrannaya Literatura, Moscow, 1961).
5. B. P. Demidovich, Lectures on Theory of Mathematical Stability (Nauka, Moscow, 1967).