8th International Conference on Nonlinear Functional Analysis and Applications, Chinju, South Korea, 9 - 13 August 2004, vol.5, pp.127-135, (Full Text)
In this paper, we present some Sufficient conditions under which all solutions of the fourth order nonlinear vector differential equation X-(4) + Phi(X)X + F(X, X)(X) triple over dot + G(X) + H(X) = P(t, X, X, X, X) are ultimately bounded.