2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/97205For a Lie groupoid G we prove an analogous of the Baker-Campbell-Hausdorff formula and we calculate the structure functions of the Lie algebroid associated to G.8 pages, in french, LaTeX 2e, submitted to Revue Roumaine de Math. Pures et AppliDifferential GeometryGroup TheorySymplectic Geometry22A22 (Primary); 58H05, 20L05 (Secondary)text