Echo tracer dispersion in flows of polymer solutions through porous media: A tool for detecting weak permeability heterogeneities? A. D'Onofrio, V.M. Freytes, M. Rosen, C. Allain and J.P. HulinEur. Phys. J. E, 7 3 (2002) 251-259DOI: https://doi.org/10.1140/epje/i200101142