Gopalsamy, K. Nonoscillatory differential equations with retarded and advanced arguments. (English) Zbl 0589.34053 Q. Appl. Math. 43, 211-214 (1985). Summary: Sufficient conditions are derived for a vector-matrix system of the form \[ \frac{d^ nX(t)}{dt^ n}+(-1)^{n-1}[P(t)X(t-\tau_ 1(t))+Q(t)X(t+\tau_ 2(\quad t))]=0 \] to be nonoscillatory. Cited in 4 Documents MSC: 34K99 Functional-differential equations (including equations with delayed, advanced or state-dependent argument) 34C10 Oscillation theory, zeros, disconjugacy and comparison theory for ordinary differential equations Keywords:nth order differential equation; vector-matrix system PDFBibTeX XMLCite \textit{K. Gopalsamy}, Q. Appl. Math. 43, 211--214 (1985; Zbl 0589.34053) Full Text: DOI