@article{10_4171_ggd_41,
     author = {Simon Thomas},
     title = {On the complexity of the quasi-isometry and virtual isomorphism problems for finitely generated groups},
     journal = {Groups, geometry, and dynamics},
     pages = {281--307},
     year = {2008},
     volume = {2},
     number = {2},
     doi = {10.4171/ggd/41},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/ggd/41/}
}