"NON-CENTRAL" PEAKS IN LIGHT SCATTERING SPECTRA OF LITHIUM TANTALATE AND QUARTZ AT PHASE TRANSITION V.S. Gorelik, B.S. Umarov et M. Umarov J. Phys. Colloques, 42 C6 (1981) C6-764-C6-766 DOI: 10.1051/jphyscol:19816225