Optical evidence for the proximity to a spin-density-wave metallic state in Na0.7CoO2 G. Caimi, L. Degiorgi, H. Berger, N. Barisic, L. Forró and F. Bussy Eur. Phys. J. B, 40 3 (2004) 231-234 Published online: 09 September 2004 DOI: 10.1140/epjb/e2004-00275-9