In a recent paper [6] the last two authors of this article introduced a class of function spaces associated with the one-dimensional torus T. They showed that the Fourier series of each function f that belongs to one of these spaces converges to f (x) a.e. Moreover, they indicated that the motion of entropy is closely related to the study of these spaces. These features are not restricted to the one-dimenslonal case. In this paper, in fact, we show how these ideas can be used to study the convergence of Bochner-Riesz means of multiple Fourier series at the "critical index".