@article{ETNA_1997__6__a8,
     author = {Brandt, A. and Livshits, I.},
     title = {Wave-ray multigrid method for standing wave equations},
     journal = {Electronic transactions on numerical analysis},
     pages = {162--181},
     publisher = {mathdoc},
     volume = {6},
     year = {1997},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ETNA_1997__6__a8/}
}