Comparison method for systems of differential equations with a rapidly rotating phase
English version (Springer): Ukrainian Mathematical Journal 34 (1982), no. 4, pp 369-374.
Citation Example: Matviichuk K. S. Comparison method for systems of differential equations with a rapidly rotating phase // Ukr. Mat. Zh. - 1982. - 34, № 4. - pp. 456—461.
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