@article{CRMATH_2003__337_5_303_0,
     author = {Nikolov, Nikolay and Segal, Dan},
     title = {Finite index subgroups in profinite groups},
     journal = {Comptes Rendus. Math\'ematique},
     pages = {303--308},
     publisher = {Elsevier},
     volume = {337},
     number = {5},
     year = {2003},
     doi = {10.1016/S1631-073X(03)00349-2},
     language = {en},
     url = {http://www.numdam.org/articles/10.1016/S1631-073X(03)00349-2/}
}