Naranjo del Val, Juan CarlosPirola, Gian PietroBarja, M.A.2023-05-022023-05-0220071056-3911https://hdl.handle.net/2445/197440We study the topological index of some irregular surfaces that we call generalized Lagrangian. We show that under certain hypotheses on the base locus of the Lagrangian system the topological index is non-negative. For the minimal surfaces of general type with $q=4$ and $p_g=5$ we prove the same statement without any hypothesis.24 p.application/pdfengcc-by-nc-nd (c) University Press Inc., 2007https://creativecommons.org/licenses/by-nc-nd/4.0/HomologiaGeometria algebraicaHomologyAlgebraic geometryinfo:eu-repo/semantics/article5546112023-05-02info:eu-repo/semantics/openAccess