Bukanay, N.U., A.E. Mirzakulova, M.K. Dauylbayev, and K.T. Konisbayeva. “A Boundary Jumps Phenomenon in the Integral Boundary Value Problem for Singularly Perturbed Differential Equations”. Bulletin of the Karaganda University. Mathematics Series 98, no. 2 (June 30, 2020): 46–58. Accessed August 25, 2025. https://mts.buketov.edu.kz/index.php/mathematics-vestnik/article/view/357.