Bugir, M. K. Mamman’s theorem for systems of first order differential equations. (Russian. English summary) Zbl 0715.34063 Dokl. Akad. Nauk Ukr. SSR, Ser. A 1990, No. 9, 9-12 (1990). Reviewer: J.JarnĂk MSC: 34C10 PDF BibTeX XML Cite \textit{M. K. Bugir}, Dokl. Akad. Nauk Ukr. SSR, Ser. A 1990, No. 9, 9--12 (1990; Zbl 0715.34063)
Bugir, M. K. Some approach to the investigation of the oscillability of partial differential equations. (Russian. English summary) Zbl 0672.35002 Dokl. Akad. Nauk Ukr. SSR, Ser. A 1988, No. 3, 9-12 (1988). MSC: 35B05 35A22 PDF BibTeX XML Cite \textit{M. K. Bugir}, Dokl. Akad. Nauk Ukr. SSR, Ser. A 1988, No. 3, 9--12 (1988; Zbl 0672.35002)
Dobrotvor, I. G.; Bugir, M. K. An oscillation criterion for the solutions of fourth order partial differential equations. (Russian. English summary) Zbl 0668.35004 Dokl. Akad. Nauk Ukr. SSR, Ser. A 1988, No. 5, 9-11 (1988). Reviewer: J.Appell MSC: 35B05 35G99 PDF BibTeX XML Cite \textit{I. G. Dobrotvor} and \textit{M. K. Bugir}, Dokl. Akad. Nauk Ukr. SSR, Ser. A 1988, No. 5, 9--11 (1988; Zbl 0668.35004)