Korol’I. I., and RontoM. I. “Investigation and Solution of Boundary-Value Problems With Parameters by Numerical-Analytic Method”. Ukrains’kyi Matematychnyi Zhurnal 46, no. 8 (August 25, 1994): 1031–1042. Accessed November 24, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/5656.