[1] Š. Bolohoroc: Oscillatory Solutions of Certain nonlinear differential equations of second order. Mat. Fyz. Časopis Sloven. Akad. Vied, 11 (1961), 250-255.

[2] T. A. Čanturija: Integral Criteria of oscillation of solutions of linear differential equations of higher order. Differ. Urav., XVI, 3 (1980), 470-482 (Russian). MR 0569776

[3] L. Erbe: Oscillation criteria for second order nonlinear delay equation. Canad. Math. Bull. 16 (1973), 49-56. DOI 10.4153/CMB-1973-011-1 | MR 0324173

[4] S. R. Grace, B. S. Lalli: Oscillation theorems for nth order delay differential equations. J. Math. Anal. Appl, 91 (1983), 352-366. DOI 10.1016/0022-247X(83)90157-9 | MR 0690876 | Zbl 0546.34055

[5] I. V. Kamenev: Some specifically nonlinear oscillation theorems. Mat. Zamentki, 10 (1971), 129-134 (Russian). MR 0287077

[6] T. Kura: Oscillation theorems for a second order sublinear ordinary differential equation. Proc. Amer. Math. Soc., 84 (1982), 535-538. DOI 10.1090/S0002-9939-1982-0643744-8 | MR 0643744 | Zbl 0488.34022

[7] Ch. G. Philos: A new criterion for the oscillatory and asymptotic behavior of delay differential equations. Bull. Acad. Pol. Ser. Sci. Mat., 29 (1981), 367-370. MR 0640329 | Zbl 0482.34056

[8] J. Ohriska: Oscillation of second order delay and ordinary differential equation. Czech. Math. J., 34 (109) 1984, 107-112. MR 0731983 | Zbl 0543.34054

[9] J. S. W. Wong: Oscillation theorems for second order nonlinear differential equations. Bull. Inst. math. Acad. Sinica, 3 (1975), 283 - 309. MR 0390372 | Zbl 0316.34035