BAINOV, D., V. PETROV, and V. PROYTCHEVA. “ASYMPTOTIC BEHAVIOUR OF SECOND ORDER NEUTRAL DIFFERENTIAL EQUATIONS WITH ‘MAXIMA’”. Tamkang Journal of Mathematics 26, no. 3 (September 1, 1995): 267–275. Accessed May 1, 2024. https://journals.math.tku.edu.tw/index.php/TKJM/article/view/4406.