@article{EJDE_1996__1996_11_a0,
     author = {Pflaum,  Christoph},
     title = {On the regularity of elliptic differential equations using symmetry techniques and suitable discrete spaces},
     journal = {Electronic journal of differential equations},
     year = {1996},
     volume = {1996},
     number = {11},
     zbl = {0885.35019},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_1996__1996_11_a0/}
}