ULTRASONIC PHONONS IN Hg0.8Mn0.2Te : DEPENDENCES OF ELASTIC MODULI ON PRESSURE AND TEMPERATURE M.H. Chao et R.J. Sladek J. Phys. Colloques, 42 C6 (1981) C6-667-C6-669 DOI: 10.1051/jphyscol:19816195