1.
Kashpirovskii AI, Mytnik YV. Approximation of solutions of operator-differential equations by operator polynomials. Ukr. Mat. Zhurn. [Internet]. 1998Nov.25 [cited 2024May19];50(11):1506–1516. Available from: https://umj.imath.kiev.ua/index.php/umj/article/view/4802