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4. S. I. Bezrodnykh and V. I. Vlasov, in International Conference “Differential Equations and Related Questions Dedicated to theMemory of I. G. Petrovskii”, Moscow, May 21–26, 2007, Abstracts of papers, pp. 36 [in Russian].
5. S. I. Bezrodnykh, in III International Conference “Mathematical Ideas of P. L. Chebyshev and Their Application to Modern Problems of Natural Science”, Obninsk, May 14–18, 2006, Abstracts of papers (2006), pp. 18–19 [in Russian].