Yessenbayeva G, Yesbayev A, Syzdykova N, Smirnova M. On the function approximation by trigonometric polynomials and the properties of families of function classes over harmonic intervals. M [Internet]. 2023 Sep. 30 [cited 2025 Dec. 8];3(111):181-90. Available from: https://mts.buketov.edu.kz/mathematics-vestnik/article/view/592