@article{JRAM_1993__435_153486,
     author = {Francisco Bernis and Josephus Hulshof},
     title = {A very singular solution for the dual porous medium equation and the asymptotic behaviour of general solutions.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {1--32},
     publisher = {mathdoc},
     volume = {435},
     year = {1993},
     zbl = {0756.35038},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1993__435_153486/}
}