@article{IM_1977__41_142483,
     author = {Robert J. Zimmer},
     title = {Hyperfinite {Factors} and {Amenable} {Ergodic} {Actions.}},
     journal = {Inventiones mathematicae},
     pages = {23--32},
     publisher = {mathdoc},
     volume = {41},
     year = {1977},
     zbl = {0361.46061},
     url = {http://geodesic.mathdoc.fr/item/IM_1977__41_142483/}
}