M.M.A. El-Sheikh
Department of Mathematics,
Faculty of Science,
Taibah University,
Madina, Saudi Arabia.
Department of Mathematics,
Faculty of Science,
Menofia University,
Shebeen El-koom, Egypt.
R. A. Sallam
Department of Mathematics,
Faculty of Science,
Menofia University,
Shebeen El-koom, Egypt.
N. Mohamady
Department of Mathematics,
Faculty of Science,
Benha University,
Egypt
In this paper we are concerned with the oscillatory behavior of solutions of two general classes of second order nonlinear neutral differential equations. The obtained results improve and extend some known criteria in the literature. Two illustrative examples are given to justify our results.