@article{ETNA_2003__15__a7,
     author = {Martikainen, Janne and Rossi, Tuomo and Toivanen, Jari},
     title = {Multilevel preconditioners for {Lagrange} multipliers in domain imbedding},
     journal = {Electronic transactions on numerical analysis},
     pages = {94--105},
     publisher = {mathdoc},
     volume = {15},
     year = {2003},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ETNA_2003__15__a7/}
}