@article{EJDE_1994__1994_3_a0,
     author = {Lewis, John L.},
     title = {On critical points of $p$ harmonic functions in the plane},
     journal = {Electronic Journal of Differential Equations},
     publisher = {mathdoc},
     volume = {1994},
     number = {3},
     year = {1994},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_1994__1994_3_a0/}
}