Effective base point freeness.
Elliptic fibres on Enriques surfaces
Errata-Corrige : “Canonical surfaces with and ”
Erratum to "On complex projective surfaces with trigonal hyperplane sections".
Éventails et variétés toriques
Every rational surface is separably split.
Everywhere non reduced moduli spaces.
Existence of Rank 3 Vector Bundles with Given Chern Classes on Homogeneous Rational 3-Folds.
Explicit birational geometry of threefolds of general type, I
Let be a complex nonsingular projective 3-fold of general type. We prove and for some positive integer . A direct consequence is the birationality of the pluricanonical map for all . Besides, the canonical volume has a universal lower bound .
Extension of maps defined on many fibres.
Let S be a fibred surface. We prove that the existence of morphisms from non countably many fibres to curves implies, up to base change, the existence of a rational map from S to another surface fibred over the same base reflecting the properties of the original morphisms. Under some conditions of unicity base change is not needed and one recovers exactly the initial maps.
Extensions of vector bundles and rationality of certain moduli spaces of stable bundles.