The aim of this paper is to study the oscillatory behavior of solutions of general third order neutral delay
differential equations using a generalized Riccati transformation. We establish new sufficient conditions for oscillations of
solutions. Illustrative examples are given to support our main results. The obtained results extend and improve some
known criteria in the literature. There has been considerable interest in studying the oscillation of solutions of neutral delay differential equations
in the last two decades. Although the oscillation of third-order equations has received less attentions relatively comparing
with those of second-order, however there is an increasing interest in studying the oscillation of neutral delay third-order
equations (see [2 ], [4 ], [ 6], [ 8] )