2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/223321We study Kustin--Miller unprojections of Calabi--Yau threefolds. As an application we work out the geometric properties of Calabi--Yau threefolds defined as linear sections of determinantal varieties. We compute their Hodge numbers and describe the morphisms corresponding to the faces of their Kähler--Mori cone.corrected hodge numbers of two familiesAlgebraic Geometry14J10,14J30,14J32text