second order delay difference equation 二阶时滞差分方程

second order delay difference equations 二阶滞后差分方程

second order delay 二阶滞后

second-order delay equations 二阶时滞方程

second order delay differential equations 二阶时滞微分方程

second-order delay differential equations 二阶滞后型微分方程

Second-order time delay systems 二阶时滞系统

second-order neutral delay difference equation 二阶中立时滞差分方程组