Grace, Said R., and John R. Graef. “Oscillatory Behavior of Second Order Nonlinear differential Equations With a Sublinear Neutral Term”. Mathematical Modelling and Analysis 23, no. 2 (April 18, 2018): 217-226. Accessed December 22, 2024. https://journals.vilniustech.lt/index.php/MMA/article/view/1412.