The Neron-Severi group of a proper seminormal complex variety
arXiv:math/0511558 · doi:10.1007/s00209-008-0324-7
Abstract
We prove a Lefschetz (1,1)-Theorem for proper seminormal varieties over the complex numbers. The proof is a non-trivial geometric argument applied to the isogeny class of the Lefschetz 1-motive associated to the mixed Hodge structure on H^2.
16 pages; Mathematische Zeitschrift (2008)