“…One way of proving this fact is by considering the blow-up of S at p: indeed one has It is well-known that H-regular submanifolds are locally intrinsic Lipschitz graphs and that an integral formula can be provided for their spherical Hausdorff measure S Q−k . We resume these facts in the following statement, which summarizes several results available in the (quite vast) literature and in particular [7, Theorem 4.2], [47,Theorem 4.1] and [29, formula (43)]; see also [4,15,16,26,28,31,32,56,64,70]. It is worth recalling that the intrinsic Jacobian determinant J φ φ was introduced in Definition 3.29.…”