I. I. Korol' and M. I. Ronto, “Investigation and solution of boundary-value problems with parameters by numerical-analytic method”, Ukr. Mat. Zhurn., vol. 46, no. 8, pp. 1031–1042, Aug. 1994, Accessed: Dec. 05, 2025. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/5656