Oscillations in first-order systems with lag
English version (Springer): Ukrainian Mathematical Journal 43 (1991), no. 9, pp 1117-1123.
Citation Example: Mitropolskiy Yu. A., Nguyen Dong An, Nguyen Tien Khiem Oscillations in first-order systems with lag // Ukr. Mat. Zh. - 1991. - 43, № 9. - pp. 1193–1201.
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