LOWER BOUND FOR THE INDEX OF CONVERGENCE OF THE SINGULAR INTEGRAL IN A MULTIDIMENSIONAL ANALOGUE OF TARRY'S PROBLEM Статья Chakhkiev M.A., Tretyakov N.P., Mouhammad S.A. Italian Journal of Pure and Applied Mathematics. Forum-Editrice Universitaria Udinese SRL. Том 48. 2022. С. 433-438