On the adjunction theoretic classification of polarized varieties.
On the ampleness of for a polarized threefold
Siano una varietà algebrica proiettiva complessa non singolare tridimensionale, un fibrato lineare ampio su , e un intero. Si prova che, a meno di contrarre un numero finito di -piani di , il fibrato è ampio ad eccezione di alcuni casi esplicitamente descritti. Come applicazione si dimostra l'ampiezza del divisore di ramificazione di un qualunque rivestimento di o della quadrica liscia di .
On the canonical ring of algebraic varieties
On the Castelnuovo-Severi inequality.
On the classical characteristic linear series of plane curves with nodes and cuspidal points : two examples of Beniamino Segre
On the Clifford Index of a General (e+2)-gonal curve.
On the Complexity of the Projective Classification of Surfaces.
On the curves through an general point of a smooth surface in IP3.
On the Degree of the Discriminant Locus of a Smooth Sectional Surface of a (n + 2)-fold with Nonnegative Kodaria Dimension.
On the Difference of 4-Gonal Linear Systems on some Curves
Let C = (C, g^1/4 ) be a tetragonal curve. We consider the scrollar invariants e1 , e2 , e3 of g^1/4 . We prove that if W^1/4 (C) is a non-singular variety, then every g^1/4 ∈ W^1/4 (C) has the same scrollar invariants.
On the dimension of secant varieties
In this paper we generalize Zak’s theorems on tangencies and on linear normality as well as Zak’s definition and classification of Severi varieties. In particular we find sharp lower bounds for the dimension of higher secant varieties of a given variety under suitable regularity assumptions on , and we classify varieties for which the bound is attained.
On the dimension of the adjoint linear system for threefolds
On the discriminant locus of an ample and spanned line bundle.
On the discriminant variety of a projective manifold.
On the fixed part of certain linear systems on surfaces
On the fundamental group of the complement of a divisor in a homogeneous space.
On the generalized theta divisor.
On the generic injectivity of the Gauss map in positive characteristic.
On the Geometrie Genera of Projective Curves.
On the geometry of algebraic curves having many real components.
We show that there is a large class of nonspecial effective divisors of relatively small degree on real algebraic curves having many real components i.e. on M-curves. We apply to 1. complete linear systems on M-curves containing divisors with entirely real support, and 2. morphisms of M-curves into P1.