@article{EJDE_1997__1997__a24,
     author = {Palagachev, Dian K. and Popivanov, Peter R.},
     title = {Sub-elliptic boundary value problems for quasilinear operators},
     journal = {Electronic Journal of Differential Equations},
     publisher = {mathdoc},
     volume = {1997},
     year = {1997},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_1997__1997__a24/}
}