Existence of a nonzero periodic solution of a singularly perturbed system of ordinary differential equations
English version (Springer): Ukrainian Mathematical Journal 41 (1989), no. 10, pp 1133-1137.
Citation Example: Terekhin M. T., Vansovich M. O. Existence of a nonzero periodic solution of a singularly perturbed system of ordinary differential equations // Ukr. Mat. Zh. - 1989. - 41, № 10. - pp. 1318–1322.
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