@article{10_4007_annals_2012_175_1_11,
     author = {Igor Mineyev},
     title = {Submultiplicativity and the {Hanna} {Neumann} {Conjecture}},
     journal = {Annals of mathematics},
     pages = {393--414},
     publisher = {mathdoc},
     volume = {175},
     number = {1},
     year = {2012},
     doi = {10.4007/annals.2012.175.1.11},
     mrnumber = {2874647},
     zbl = {06014080},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4007/annals.2012.175.1.11/}
}