Serdyuk, A. S., and I. V. Sokolenko. “Approximation by Fourier Sums in Classes of Weyl – Nagy Differentiable Functions With High Exponent of Smoothness”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 74, no. 5, June 2022, pp. 685 -00, doi:10.37863/umzh.v74i5.7136.