@article{10_4171_ggd_169,
     author = {Giovanni Gandini},
     title = {Cohomological invariants and  the classifying space  for proper actions},
     journal = {Groups, geometry, and dynamics},
     pages = {659--675},
     year = {2012},
     volume = {6},
     number = {4},
     doi = {10.4171/ggd/169},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/ggd/169/}
}