@article{EJDE_2004__2004__a190,
     author = {Karatson,  Janos},
     title = {Constructive {Sobolev} gradient preconditioning for semilinear elliptic systems},
     journal = {Electronic journal of differential equations},
     year = {2004},
     volume = {2004},
     zbl = {1109.65308},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_2004__2004__a190/}
}