[1] Li L. M.:
Periodic solution for a class of higher dimensional nonautonomous system. Acta Math. Appl. Sinica 12(3)(1989), 272–280.
MR 1033579
[2] Wang K.:
Periodic solutions to a class differential equations with deviating argument. Acta Math. Sinica 37(3)(1994), 409–413.
MR 1289267
[3] Wang Q. Y.:
Existence, uniqueness and stability of periodic solutions. Chinese Ann. Mathematics 15A(5)(1994), 537–545.
MR 1332635 |
Zbl 0817.34025
[4] Tang Y. B.:
Periodic solutions of a class of neutral type functional differential equation. Acta Math. Appl. Sinica, 23(3)(2000), 321–328.
MR 1797627
[5] Wang G. Q., Cheng S. S.:
A priori bounds for periodic solutions of a delay Rayleigh equation. Appl. Math. Lett. 12(1999), 41–44.
MR 1749731 |
Zbl 0980.34068
[6] Wang G. Q., Yan J. R.: Existence of periodic solutions for $n$-th order nonlinear delay differential equation. Far East J. Appl. Math. 3(1999), 129–134.
[7] Wang G. Q., Cheng S. S.:
A priori bounds for periodic solutions of a delay Rayleigh equation with damping. Tamkang J. Math. 34(3)(2003), 293–298.
MR 2002244 |
Zbl 1051.34057
[8] Wang G. Q., Yan J. R.:
Existence theorem of periodic positive solutions for the Rayleigh equation of retarded type. Portugaliae Math. 57(3)(2000), 153–160.
MR 1759811 |
Zbl 0963.34069
[9] Wang G. Q., Yan J. R.:
Existence of periodic solutions for second order nonlinear neutral delay equations. Acta Math. Sinica 47(2)(2004), 370–384.
MR 2074362
[10] Gaines R. E., Mawhin J. L.:
Coincidence degree and nonlinear differential equations. Lecture Notes in Math. 568, Springer, 1977.
MR 0637067 |
Zbl 0339.47031
[11] Reissig R., Sasone G., Conti R.: Nonlinear equations of higher order. Noordhoff Inter. Pub. Leyden, 1974.
[12] Vidyasagar M.: Nonlinear system analysis. Prentice Hall Inc., 1978.