[1]. Wang Na, Existence of periodic solutions for a nonlinear functional diffential equation in losslesstransmission line model，Chinese Physics B, 2012，21(1): 010202. [2].汪娜,倪明康. 经典物理中的扰动时滞模型解，物理学报. 2011，60(5)：050203 [3].WANG Na，The Existence and Uniqueness of Periodic Solutions for a Kind of Liénard Equation with a Deviating Argument，Chinese Quarterly Journal of Mathematics，2010, 25 (1): 74—80. [4]. WANG Na,Sufficient Conditions for the Existence of Periodic Solutions to Some Third Order Differential Equations with Deviating Argument,Mathematica Applicata,2008,21(4):661-670. [5]. Wang Na, Approximate Analytic Solution for a Class of Generalized Nonlinear Singularly Perturbed Time-Delay Model in the Critical Case，Chinese Quarterly Journal of Mathematics，(to be published)