A mean-square bound for the lattice discrepancy of bodies of rotation with flat points on the boundary

Let B denote a three-dimensional body of rotation, with respect to one coordinate axis, whose boundary is sufficiently smooth and of bounded nonzero Gaussian curvature throughout, except for the two boundary points on the axis of rotation, where the curvature may vanish. For a large real variable t, we are interested in the number A(t) of integer points in the linearly dilated body tB, in particular in the lattice discrepancy P(t) = A(t) - volume(tB). We are able to evaluate the contribution of the boundary points of curvature zero to P(t), with a remainder that is fairly small in mean-square.