2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/72410In this note we consider the behavior of linear systems of P^3 through fat points under a cubo-cubic Cremona transformation. This allows us to produce a class of special systems which we conjecture to be the only ones.4 pages, LaTeXAlgebraic Geometry14C20text