2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/68147We prove, for the form of unitary group in three variables attached to a CM extension which is compact at infinity, a level-raising theorem analogous to the one of Taylor (inv. math. 98, 265-280) in the case of a quaternion algebra. We give an application to non tempered automorphic forms.25 pages, FrenchNumber TheoryRepresentation Theory11FXXtext