1. Yu. M. Daletskii and M. G. Krein, Stability of Solutions of Differential Equations in Banach Spaces [in Russian], Nauka, Moscow (1970).
2. M. A. Krasnosel’skii, V. Sh. Burd, and Yu. S. Kolesov, Nonlinear Almost Periodic Oscillations [in Russian], Nauka, Moscow (1970).
3. J. L. Massera and J. J. Schaffer, Linear Differential Equations and Function Spaces, Academic Press, New York (1966).
4. P. Hartman, Ordinary Differential Equations, Wiley, New York (1964).
5. Yu. V. Trubnikov and A. I. Perov, Differential Equations with Monotone Nonlinearities [in Russian], Nauka i Tekhnika, Minsk (1986).