Raman Sanyal Axel Werner Günter M. Ziegler On Kalai's Conjectures Concerning Centrally Symmetric Polytopes. 183-198 2009 41 Discrete & Computational Geometry 2 http://dx.doi.org/10.1007/s00454-008-9104-8 db/journals/dcg/dcg41.html#SanyalWZ09