[1] J. R. Graef M. K. Grammatikopoulos, P. W Spikes: Growth and oscillatory behavior of solutions of a differential equation with a deviating argument. to appear. MR 0621534

[2] J. R. Graef, T. Kusano: Oscillation and nonoscillation criteria for a class of forced differential equations with deviating arguments. in preparation. Zbl 0562.34057

[3] A. Granata: Canonical factorizations of disconjugate differential operators. SIAM J. Math. Anal. 11 (1980), 160-172. MR 0556506 | Zbl 0431.34008

[4] Y. Kitamura, T. Kusano: Nonlinear oscillation of higher order functional differential equations with deviating arguments. J. Math. Anal. Appl. 77 (1980), 100-119. MR 0591264 | Zbl 0465.34044

[5] T. Kusano, H. Onose: Oscillations of functional differential equations with retarded argument. J. Differential Equations 15 (1974), 269-277. MR 0333398 | Zbl 0292.34078

[6] M. Naito: Existence and asymptotic behavior of positive solutions of differential inequalities with deviating argument. Funkcial. Ekvac. 22 (1979), 127-142. MR 0556574 | Zbl 0437.34060

[7] H. Onose: Oscillation and asymptotic behavior of solutions of retarded differential equations of arbitrary order. Hiroshima Math. J. 3 (1973), 333-360. MR 0348231 | Zbl 0299.34098

[8] V. N. Ševelo, N. V. Vareh: On the oscillation of solutions of the equation $[r(t) y^{(n-1)} (t )]' + p(t) f(y(\tau (t))) = 0$. Ukrain. Mat. Ž. 25 (1973), 724-731. (Russian). MR 0326110

[9] V. N. Ševelo: Oscillation of Solutions of Differential Equations with Deviating Arguments. Naukova Dumka, Kiev, 1978. (Russian). MR 0492732

[10] B. Singh: A necessary and sufficient condition for the oscillation of an even order nonlinear delay differential equation. Canad. J. Math. 25 (1973), 1078-1089. MR 0330706 | Zbl 0273.34047

[11] B. Singh: Impact of delays on oscillations in general functional equations. Hiroshima Math. J. 5 (1975), 351-361. MR 0422822

[12] W. F. Trench: Canonical forms and principal systems for general disconjugate equations. Trans. Amer. Math. Soc. 189 (1974), 319-327. MR 0330632 | Zbl 0289.34051