Mixed layer – structured ferroelectrics on the basis of Bi4Ti3O12 D. Machura, Z. Surowiak, J. Rymarczyk and J. Ilczuk Eur. Phys. J. Special Topics, 154 (2008) 135-138 Published online: 15 March 2008 DOI: 10.1140/epjst/e2008-00532-3