@article{EJDE_2011__2011__a37,
     author = {Turki,  Sameh},
     title = {Existence of continuous positive solutions for some nonlinear polyharmonic systems outside the unit ball},
     journal = {Electronic journal of differential equations},
     year = {2011},
     volume = {2011},
     zbl = {1229.35063},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_2011__2011__a37/}
}