%0 Journal Article %A S. Challal %A Abdeslem Lyaghfouri %T A filtration problem through a heterogeneous porous medium %J Interfaces and free boundaries %D 2004 %P 55-79 %V 6 %N 1 %U http://geodesic.mathdoc.fr/articles/10.4171/ifb/91/ %R 10.4171/ifb/91 %F 10_4171_ifb_91