Bel’skiiD. V., and PelyukhG. P. “Asymptotic Estimates for the Solutions of a Differential-functional
equation With Linear Delay”. *Ukrains’kyi Matematychnyi Zhurnal* 71, no. 1 (January 25, 2019): 129-138. Accessed November 29, 2020. http://umj.imath.kiev.ua/index.php/umj/article/view/1424.