Feng, Binlu; Yu, Yuanhong A Lyapunov inequality for higher order functional differential equations. (Chinese. English summary) Zbl 0842.34074 J. Qufu Norm. Univ., Nat. Sci. 21, No. 3, 23-28 (1995). Summary: A Lyapunov inequality for nonlinear functional differential equations is given. Sufficient conditions are obtained which ensure that all oscillatory solutions of the equation tend to zero and all solutions of the corresponding homogeneous equation are nonoscillatory. MSC: 34K11 Oscillation theory of functional-differential equations 34C10 Oscillation theory, zeros, disconjugacy and comparison theory for ordinary differential equations Keywords:Lyapunov inequality; nonlinear functional differential equations; oscillatory solutions; nonoscillatory PDFBibTeX XMLCite \textit{B. Feng} and \textit{Y. Yu}, J. Qufu Norm. Univ., Nat. Sci. 21, No. 3, 23--28 (1995; Zbl 0842.34074)