@article{10_4171_emss_18,
     author = {Wolfgang L\"uck},
     title = {Approximating $L^2$-invariants by their classical counterparts},
     journal = {EMS surveys in mathematical sciences},
     pages = {269--344},
     year = {2016},
     volume = {3},
     number = {2},
     doi = {10.4171/emss/18},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/emss/18/}
}