“…More precisely, they proved in [4], [5] that there is a function h(a) defined for a ≤ 0, satisfying h(0) = 0, a < h(a) < a + 1 for a < 0, and a+1−h(a) → 0 as −a → ∞, such that for any (a, b) satisfying a < 0 and a < b < h(a), the extremal function for S(a, b) is non-radial. In a recent preprint [9] of Felli and Schneider, it is observed that this curve h(a) can be sharpened to the following:…”