@article{etna_vol24_pp103-107, author = {Ana Portilla and Yamilet Quintana and Jos\'e M. Rodr{\'i}guez and Eva Tour{\'i}s}, title = {Weierstrass' theorem in weighted Sobolev spaces with $k$ derivatives: announcement of results}, journal = {Electron. Trans. Numer. Anal.}, volume = {24}, year = {2006}, pages = {103--107}, }