$a Konečnye integral'nye preobrazovaniâ [...] / N. A. Martynenko, L. M. Pustyl'nikov. - Moskva, 1986. $b Red.
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$a Phase portraits of control dynamical systems / by Anatoliy G. Butkovskiy. - Dordrecht, cop. 1991. $b (Lab. for Distributed Parameter Systems, Inst. of Control Sciences, Moscow)