Optical properties of the charge-density-wave polychalcogenide compounds R 2Te 5 (R=Nd, Sm and Gd) F. Pfuner, L. Degiorgi, K. Y. Shin and I. R. Fisher Eur. Phys. J. B, 63 1 (2008) 11-16 Published online: 30 May 2008 DOI: 10.1140/epjb/e2008-00205-y