1. Reissing R, Sansone G, Conti R.Nonlinear Differential Equations of Higher Order [M]. Groningen: Noordhoff, 1974.
2. Abou-el-ela A M A, Sadek A I. On the asymptotic behaviour of solutions of certain nonautonomous differential equations[J].J Math Anal Appl, 1999,237: 360–375.
3. Yoshizawa T.Stability Theorem by Liapunov Second Method [M]. Tokyo: The Mathematical Society of Japan, 1966.
4. Abou-el-ela A M A, Sadek a I. On complete stability of the solutions of nonlinear differential equations of the fifth-order[A]. In:Proceedings of the Assiut First International Conference [C]. Assiut: Assiut University, 1990, 14–25.
5. Abou-el-ela A M A, Sadek A I. On boundedness and periodicity of certain differential equation of the fifth-order[J].Z Anal Anwendungen, 1992,11 (2): 237–244.