Bugir, M. K. The connection between the nonoscillatory nature of solutions and ill- posed boundary value problems for fourth-order equations of elliptic type. (English. Russian original) Zbl 0765.35057 Sov. Math., Dokl. 44, No. 1, 269-272 (1992); translation from Dokl. Akad. Nauk SSSR 319, No. 5, 1053-1056 (1991). MSC: 35R25 35J40 35G15 PDF BibTeX XML Cite \textit{M. K. Bugir}, Sov. Math., Dokl. 44, No. 1, 269--272 (1991; Zbl 0765.35057); translation from Dokl. Akad. Nauk SSSR 319, No. 5, 1053--1056 (1991)
Bugir, M. K. Oscillation conditions for equations of the form \(L^ ku+c(x,u)=f(x)\). (English. Russian original) Zbl 0701.35008 Sov. Math., Dokl. 39, No. 1, 104-107 (1989); translation from Dokl. Akad. Nauk SSSR 304, No. 3, 538-541 (1989). Reviewer: A.Venkov MSC: 35B05 35J60 PDF BibTeX XML Cite \textit{M. K. Bugir}, Sov. Math., Dokl. 39, No. 1, 104--107 (1989; Zbl 0701.35008); translation from Dokl. Akad. Nauk SSSR 304, No. 3, 538--541 (1989)