2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/150188After the work of Bloch and Srinivas on correspondences and algebraic cycles we begin the study of a birational class of algebraic varieties determined by the property that a multiple of the diagonal is rationally equivalent to a cycle supported on proper subschemes.12 pages, LaTeXAlgebraic Geometrytext