Atlasiuk, O. M., and V. A. Mikhailets. “Fredholm One-Dimensional Boundary-Value Problems in Sobolev Spaces”. Ukrains’kyi Matematychnyi Zhurnal 70, no. 10 (October 25, 2018): 1324–1333. Accessed December 6, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/1638.