@article{MS2_1978__43_166607,
     author = {Uffe Haagerup},
     title = {On the dual weights for crossed products of von {Neumann} algebras {I.}},
     journal = {Mathematica Scandinavica},
     pages = {99--118},
     year = {1978},
     volume = {43},
     zbl = {0405.46052},
     url = {http://geodesic.mathdoc.fr/item/MS2_1978__43_166607/}
}