Grabova UZ. Approximation of the classes of convolutions of periodic functions by Zygmund sums in integral metrics . Dopov. Nac. akad. nauk Ukr. [Internet]. 2014 Sep. 28 [cited 2026 Jun. 20];(9):13-8. Available from: https://nasu-periodicals.org.ua/index.php/dp/article/view/16677