K. Pozharska, A. Romanyuk, S. Yanchenko, “Найкращі наближення класів періодичних функцій багатьох змінних з обмеженою домінуючою мішаною похідною”, Ukr. Mat. Zhurn., 76:7 (2024), 1007
J. Milaré, A.K. Kushpel, S.A. Tozoni, “Estimates of entropy for multiplier operators of systems of orthonormal functions”, Journal of Approximation Theory, 285 (2023), 105837
Svitlana Hembars'ka, Ihor Romanyuk, Oksana Fedunyk-Yaremchuk, “Characteristics of the linear and nonlinear approximations of the Nikol'skii-Besov-type classes of periodic functions of several variables”, UMB, 20:2 (2023), 161
Anatolii S. Romanyuk, Serhii Ya. Yanchenko, “Estimates for the entropy numbers of the Nikol'skii–Besov classes of functions with mixed smoothness in the space of quasi‐continuous functions”, Mathematische Nachrichten, 296:6 (2023), 2575
Alexander Kushpel, “Lower bounds of cowidths and widths of multiplier operators”, Journal of Complexity, 69 (2022), 101614
V. K. Nguyen, V. D. Nguyen, “Best n-Term Approximation of Diagonal Operators and Application to Function Spaces with Mixed Smoothness”, Anal Math, 48:4 (2022), 1127
Б. С. Кашин, “Об оценках снизу $m$-членных приближений в метрике дискретного пространства $L_n^0$”, УМН, 76:5(461) (2021), 199–200 ; B. S. Kashin, “Lower bounds for $m$-term approximations in the metric of the discrete space $L_n^0$”, Russian Math. Surveys, 76:5 (2021), 933–935
Kateryna V. Pozharska, “Entropy Numbers of the Nikol'skii—Besov-type Classes of Periodic Functions of many Variables”, J Math Sci, 241:1 (2019), 64
Temlyakov V., “on the Entropy Numbers of the Mixed Smoothness Function Classes”, J. Approx. Theory, 217 (2017), 26–56
Romanyuk A.S., “Entropy Numbers and Widths For the Classes of Periodic Functions of Many Variables”, Ukr. Math. J., 68:10 (2017), 1620–1636