1.
Stepanets OI. Approximation Characteristics of the Spaces $S_p^{ϕ}$ in Different Metrics. Ukr. Mat. Zhurn. [Internet]. 2001Aug.25 [cited 2024May19];53(8):1121-46. Available from: https://umj.imath.kiev.ua/index.php/umj/article/view/4331