Intrinsically Lipschitz functions with normal target in Carnot groups

We provide a Rademacher theorem for intrinsically Lipschitz functions \(\phi\colon U\subseteq\mathbf{W}\to\mathbf{L}\), where \(U\) is Borel set, \(\mathbf{W}\) and \(\mathbf{L}\) are complementary subgroups of Carnot group, we require that normal subgroup. Our hypotheses satisfied example when horizontal Moreover, an area formula this class functions.