@article{GFA_1994__4_6_58171,
     author = {W. L\"uck},
     title = {Approximation {L2-invariants} by {Their} {Finite-Dimensional} {Analogues.}},
     journal = {Geometric and functional analysis},
     pages = {455--482},
     publisher = {mathdoc},
     volume = {4},
     number = {6},
     year = {1994},
     zbl = {0853.57021},
     url = {http://geodesic.mathdoc.fr/item/GFA_1994__4_6_58171/}
}