The spin-entropy enhancement induced by Ce doping in Ca3Co4O9+δG. D. Tang, X. N. Xu, C. P. Tang, Z. H. Wang, Y. He, L. Qiu, L. Y. Lv, L. Xing and Y. W. DuEPL, 91 1 (2010) 17002DOI: https://doi.org/10.1209/0295-5075/91/17002