A frequency criterion in the simplest critical case for absolute stability of controllable systems with many nonlinearities
English version (Springer): Ukrainian Mathematical Journal 20 (1968), no. 4, pp 455-460.
Citation Example: Ostapov Yu. G. A frequency criterion in the simplest critical case for absolute stability of controllable systems with many nonlinearities // Ukr. Mat. Zh. - 1968. - 20, № 4. - pp. 528–534.
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