Comment on the paper: 'Interval criteria for oscillation of second-order nonlinear neutral differential equations' [Comput. Math. Appl. 46 (5-6) (2003)903-918]

摘要

The paper [1] is concerned with a class of general type second-order nonlinear neutral differential equations under some assumptions. The authors mentioned therein that they established new oscillation criteria which can be regarded as improved and extended some known results by using the Riccati technique. Although the greater part of the published paper is very interesting and well-organized, there are some mistakes in it. The mistakes are caused by the following false Assertion A that was used in the Lemma 1.