A NEUTRON SCATTERING STUDY OF THE DENSITY OF VIBRATIONAL STATES OF FRACTAL SILICA AEROGELS G. CODDENS, R. VACHER, T. WOIGNIER, J. PELOUS et E. COURTENSJ. Phys. Colloques, 50 C4 (1989) C4-151-C4-156DOI: https://doi.org/10.1051/jphyscol:1989424