OBSERVATION OF PRETRANSITIONAL EFFECTS ON THE SHAPE OF THE E2 (17 cm-1 ) OPTICAL MODE IN β-Ag1 BY RAMAN SPECTROSCOPY E. Cazzanelli, A. Fontana, G. Mariotto, F. Rocca et M. P. FontanaJ. Phys. Colloques, 42 C6 (1981) C6-776-C6-778DOI: https://doi.org/10.1051/jphyscol:19816229