2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/120561We give a simple characterization of Mackenzie's double Lie algebroids in terms of homological vector fields. Application to the `Drinfeld double' of Lie bialgebroids is given and an extension to the multiple case is suggested.LaTeX, 30 pages. Second version: some editing aimed at clarifying the expositionDifferential GeometryMathematical PhysicsSymplectic Geometrytext