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ZernovA. E.; KuzinaY. V. Asymptotic Behavior of Solutions of the Cauchy Problem <em class="a-Plus-plus">x</em>′ = <em class="a-Plus-plus">f</em>(<em class="a-Plus-plus">t</em>, <em class="a-Plus-plus">x</em>, <em class="a-Plus-plus">x</em>′), <em class="a-Plus-plus">x</Em&gt;(0) = 0. Ukr. Mat. Zhurn. 2002, 54, 1698-1703.