V. Kargl, A. Mirmelstein, P. Boeni, D. Sheptyakov, A. Amato, S. Kazakov, J. Karpinski, A. Erb: Neutron diffraction, specific heat and mu SR study of the spin-chain compounds Ca(2+x)Y(2-x)Cu(5)O(10). 2004Physica B-Condensed Matter: 350. ISBN 0921-4526 http://dx.doi.org/10.1016/j.physb.2004.03.063