The authors consider a system of nonlinear differential equations containing a small parameter with undifferentiated right parts of types (1) and (37). Making some assumptions, the existence unique and asymptotic stability of a periodic solution is proved for such systems, and an estimate is found for the difference between the exact solution of the systems under consideration and their first approximation, which can be found without any essential difficulty.
Citation Example:Lykova O. B., Mitropolskiy Yu. A. On Periodic Solutions of Systems of Nonlinear Equations with a Small Parameter // Ukr. Mat. Zh. - 1960. - 12, № 4. - pp. 391 - 401.