@article{10_4171_ggd_101,
     author = {Martin R. Bridson and Daniel Groves and Jonathan A. Hillman and Gaven J. Martin},
     title = {Cofinitely {Hopfian} groups, open mappings and knot complements},
     journal = {Groups, geometry, and dynamics},
     pages = {693--707},
     year = {2010},
     volume = {4},
     number = {4},
     doi = {10.4171/ggd/101},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/ggd/101/}
}