On the oscillation of certain third order nonlinear functional differential equations

We offer some sufficient conditions for the oscillation of all solutions of third order nonlinear functional differential equations of the formddta(t)d2dt2x(t)α+q(t)f(x[g(t)])=0andddta(t)d2dt2x(t)α=q(t)f(x[g(t)])+p(t)h(x[σ(t)]),when ∫∞a-1/α(s)ds<∞∫∞a-1/α(s)ds<∞. The case when ∫∞a-1/α(s)ds=∞∫∞a-1/α(s)ds=∞ is also included.