2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/125616We prove that any base space of Riemannian submersion from a compact Lie group (with bi-invariant metric) must have a basic property previously known for normal biquotients; namely, any zero-curvature plane exponentiates to a flat.Differential GeometryMetric Geometry53C20text