Abstract
The purpose of this paper is to give oscillation criteria for the third order delay nonlinear differential equation
[a(2)(t){(a(1)(t)(x'(t))(alpha 1))'}(alpha 2)]' + q(t)f(x(g(t)))=0,
via comparison with some first differential equations whose oscillatory characters are known. Our results generalize and improve some known results for oscillation of third order nonlinear differential equations. Some examples are given to illustrate the main results.