ULTRASONIC ATTENUATION AND SOUND VELOCITY ANOMALIES BELOW 5 K IN LaAl2 S. Ewert, A. Hof, D. Lenz et H. Schmid J. Phys. Colloques, 42 C5 (1981) C5-695-C5-700 DOI: 10.1051/jphyscol:19815107