Aviltay, N., and M. Akhmet. “Asymptotic Behavior of the Solution of the Integral Boundary Value Problem for Singularly Perturbed Integro-Differential Equations”. Journal of Mathematics, Mechanics and Computer Science, vol. 112, no. 4, Dec. 2021, doi:10.26577/JMMCS.2021.v112.i4.02.