Photoacoustic evaluation of molecular weight and crosslinking effects on thermal diffusivity in Poly(N-vinyl-2-pirrolidone) R. Saavedra, N. Gatica, J.E. Morales and A. Cruz-Orea J. Phys. IV France, 125 (2005) 281-283 DOI: 10.1051/jp4:2005125067