1. Anosov D.V. (1960) Averaging in systems of ordinary differential equations with rapidly oscillating solutions, Izv. Akad. Nauk SSSR, Ser. Mat., 24, pp. 721–742 (Russian)
2. Arnold V.I. (1978) Mathematical methods of classical mechanics. Springer, New York
3. Arnold V.I. (1983) Geometrical methods in the theory of ordinary differential equations. Springer, New York
4. Arnold V.I. (1963) Small denominators and problems of stability of motion in classical and celestial mechanics, Usp. Mat. Nauk, 18, pp. 91–192 (Russian) [English transi.: (1963) Russ. Math. Surv., 18. pp. 85–192]
5. Arnold V.I. (1965) Conditions of the applicability and estimates of the error of averaging method for systems which pass through states of resonance in the course of their evolution, Dokl. Akad. Nauk SSSR, 161, pp. 9–12 (Russian) [English transi.: (1965) Soviet Math. Dokl., 6 pp. 331–334]