Kharkevych Y, Shutovskyi A. Approximation of functions from Hӧlder class by biharmonic Poisson integrals. Carpathian Math. Publ. [Internet]. 2024 Dec. 30 [cited 2025 Jan. 15];16(2):631-7. Available from: https://journals.pnu.edu.ua/index.php/cmp/article/view/8243