The order of approximation functions of several variables - singular integrals

In solving the problem of determining saturation classes, a number of important results were obtained by P.I. Romanovsky, I.P. Natanson, D.K. Fadeev, B.I. Kornblum, F. Kharshiladze, A. Turetsky, P.L. Butzer, R. Nessel, R.G. Mamedov and others. Using the Fourier transform method, Butzer [1-2], R.G. Mamedov [ 4] and others determined the order and saturation class of various singular integrals and linear operators in the spaceImage not available. The main results obtained in recent years by various authors on the solution of the saturation problem are described in detail in the monographs of R.G. Mamedov [ 4] and Butzer-Berenz [ 3]. In this paper, the order and class of saturation are determined Image not available -singular integrals of general form in the metric of the spaceImage not available. The results obtained are applied to determining the order and saturation class of a specific singular integral