@article{JEMS_2006_8_3_a5,
     author = {Guillermo Reyes and Juan Luis V\'azquez},
     title = {A weighted symmetrization for nonlinear elliptic and parabolic equations in inhomogeneous media},
     journal = {Journal of the European Mathematical Society},
     pages = {531--554},
     publisher = {mathdoc},
     volume = {8},
     number = {3},
     year = {2006},
     doi = {10.4171/jems/66},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/jems/66/}
}