[1] M. Hanan: Oscillation criteria for third-order linear differential equations. Pacific J. Math. 11 (1961), 919-944. MR 0145160 | Zbl 0104.30901

[2] M. Greguš: Linear Differential Equation of the Зrd Order. (Czech). Veda, Bratislava 1981.

[3] G. D. Jones: Oscillation properties of third order differential equations. Rocky Mountain Journal of Math. 3, 1973, 507-513. MR 0355193 | Zbl 0267.34033

[4] G. D. Jones: Oscillatory behaviour of third order differential equations. Proceedings of the Amer. Math. Soc. 43, 1974, 133-136. MR 0333341

[5] A. C. Lazer: The behaviour of solutions of the diffeгential equation y" + p(x) y' + q(x) y = 0. Pacific J. Math. 17, 1966, 435-466. MR 0193332

[6] M. Ráb: Аsymptotic formulas for the solutions of lineaг differential equations of the second order. Proceedings of the Czechoslovak Conference Diff. Eqs. and Their Аppl. EQUАDIFF held in Prague 1962. Аcademia, Praha, 131-135. MR 0170064

[7] M. Švec: On various properties of the solutions of third and fourth-order linear differential equations. Proceedings of the Czechoslovak Conference Diff. Eqs. and Their Аppl. EQUАDIFF held in Prague 1962. Аcademia, Praha, 187-198. MR 0174825

[8] M. Švec: Several remarks on the Зrd order linear differential equation. (Russian), Czechoslovak Math. J. 15 (90), 1965, 42-49. MR 0171970