HYPER-RAMAN SCATTERING STUDY OF FERROELECTRIC PHASE TRANSITIONS IN SrTiO3 AND BaTiO3 K. Inoue et N. AsaiJ. Phys. Colloques, 42 C6 (1981) C6-430-C6-432DOI: https://doi.org/10.1051/jphyscol:19816126