References
- R. P. Agarwal, Difference equations and inequalities, Marcel Dekker, New York, 1992.
- R. P. Agarwal, S. R. Grace and D. O'Regan, Oscillation theory for difference and functional differential equations, Kluwer Academic Publishers, 2000.
- K. Gopalsamy, I. Gyori and G. Ladas, Oscillations of a class of delay equations with continuous and piecewise constant arguments, Funkcial Ekvac., 32(1989), 395-406.
- I. Gyori and G. Ladas, Oscillation theory of delay differential equations with applications, Clarendon Press, Oxford, 1991.
- G. Ladas and C. Qian, Comparison results and linearized oscillations for higher order difference equations, Internat. J. Math. & Math. Sci., 15(1992), 129-142. https://doi.org/10.1155/S0161171292000152
- G. Ladas, Oscillations of a equations with piecewise constant mixed arguments, Proceedings, International Conference on Differential Equations and Population Biology, Ohio University, March 21-25, New York, 1988.
- G. Ladas, Explicit conditions for the oscillation of difference equations, Journal of Mathematical Analysis and Applications, 153(1990), 276-287. https://doi.org/10.1016/0022-247X(90)90278-N
- G. Ladas, Ch. G. Philos and Y. G. Sficas, Necessary and sufficient conditions for the oscillation of difference equation, Libertas Mathematica, 9(1989), 121-125.