2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/63269In this paper we study the reduction of PEL-Shimura varieties associated to unitary groups of signature (n-1,1) in the inert and unramified case. We describe the Newton polygon and the Ekedahl-Oort stratification. We further study the associated moduli space of isogenies and use a variant of the local model to give a generic description. As an application we prove a conjecture of Blasius und Rogawski about the congruence relation if the integer n is even.42 pagesAlgebraic GeometryNumber Theory14G35, 14K10 (Primary) 14G10, 11G15, 14K02, 11G25 (Secondary)text