@article{10_4171_ggd_20,
     author = {Emmanuel D. Farjoun and R\"udiger G\"obel and Yoav Segev and Saharon Shelah},
     title = {On kernels of cellular covers},
     journal = {Groups, geometry, and dynamics},
     pages = {409--419},
     year = {2007},
     volume = {1},
     number = {4},
     doi = {10.4171/ggd/20},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/ggd/20/}
}