On Jackson-Type Inequalities for Functions Defined on a Sphere
We obtain exact estimates of the approximation in the metrics $C$ and $L_2$ of functions, that are defined on a sphere, by means of linear methods of summation of the Fourier series in spherical harmonics in the case where differential and difference properties of functions are defined in the space $L_2$.
English version (Springer): Ukrainian Mathematical Journal 57 (2005), no. 3, pp 347-363.
Citation Example: Babenko V. F., Doronin V. G., Ligun A. A., Shumeiko A. A. On Jackson-Type Inequalities for Functions Defined on a Sphere // Ukr. Mat. Zh. - 2005. - 57, № 3. - pp. 291–304.