RomanyshynI. M., and Synyts’kyiL. A. “Construction of Approximations for a Stationary Solution of a System of Singular Ordinary Differential Equations”. Ukrains’kyi Matematychnyi Zhurnal 49, no. 6 (June 25, 1997): 774–778. Accessed July 27, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/5061.