Klevchuk, I. I. “Homoclinic Points for a Singularly Perturbed System of Differential Equations With Delay”. Ukrains’kyi Matematychnyi Zhurnal 54, no. 4 (April 25, 2002): 563-567. Accessed May 19, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/4093.