Kashpirovskii, A. I., and S. M. Torba. “Characterization of the Rate of Convergence of One Approximate Method for the Solution of an Abstract Cauchy Problem”.
Ukrains’kyi Matematychnyi Zhurnal 60, no. 4 (April 25, 2008): 557–563. Accessed April 26, 2025.
https://umj.imath.kiev.ua/index.php/umj/article/view/3175.