A.Manousakis .(2003).Some remarks on spreading models and mixed tsirelson spaces,.Proceedings of the American mathematical society [online].pp.2515-2525.Available:http://www.ams.org/journals/proc/2003-131-08/S0002-9939-02-06832-6/S0002-9939-02-06832-6.pdf
We prove that if a Banach space with a bimonotone shrinkingbasis does not contain `ω1 spreading models but every block sequence of thebasis contains a further block sequence which is a c − `n1 spreading model forevery n ∈ N, then every subspace has a further subspace which is arbitrarilydistortable. We also prove that a mixed Tsirelson space T[(Sn, θn)n], suchthat θn & 0, does not contain `ω21 spreading models