2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/149808We prove that up to birational equivalence, there exists only a finite number of families of Calabi-Yau threefolds (i.e. a threefold with trivial canonical class and factorial terminal singularities) which have an elliptic fibration to a rational surface. This strengthens a result of B. Hunt that there are only a finite number of possible Euler characteristics for such threefolds.29 pages, plain TeXAlgebraic Geometrytext