AUTOMATION OF INTERNAL FRICTION MEASUREMENT APPARATUS OF INVERTED TORSION PENDULUM TYPE I. Yoshida, T. Sugai, S. Tani, M. Motegi, K. Minamida and H. Hayakawa J. Phys. Colloques, 42 C5 (1981) C5-1123-C5-1128 DOI: 10.1051/jphyscol:19815173