%0 Journal Article
%T Geometry of Banach spaces and biorthogonal systems
%A S. J. Dilworth
%A Maria Girardi
%A W. B. Johnson
%J Mathematics
%D 1999
%I arXiv
%X A separable Banach space X contains $\ell_1$ isomorphically if and only if X has a bounded wc_0^*-stable biorthogonal system. The dual of a separable Banach space X fails the Schur property if and only if X has a bounded wc_0^*-biorthogonal system.
%U http://arxiv.org/abs/math/9911156v1