[1]
Y. N. Valitskii, B. I. Golets, and T. I. Zelenyak, “Multipoint Boundary Conditions for Differential Operators”, Ukr. Mat. Zhurn., vol. 55, no. 1, pp. 126–131, Jan. 2003, Accessed: Dec. 06, 2025. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/3894