Let be a discrete group for which the classifying space for proper –actions is finite-dimensional. We find a space such that for any such , the classifying space for proper –bundles has the homotopy type of the –nullification of . We use this to deduce some results concerning and in some cases where there is a good model for we obtain information about the –nullification of .
Ramon J Flores. "Nullification functors and the homotopy type of the classifying space for proper bundles." Algebr. Geom. Topol. 5 (3) 1141 - 1172, 2005. https://doi.org/10.2140/agt.2005.5.1141