@article{IM_1977__40_142477,
     author = {Daniel Bertrand},
     title = {Sous-groupes \`a un param\`etre p-adique de vari\'et\'es de groupe.},
     journal = {Inventiones mathematicae},
     pages = {171--194},
     publisher = {mathdoc},
     volume = {40},
     year = {1977},
     zbl = {0351.22006},
     url = {http://geodesic.mathdoc.fr/item/IM_1977__40_142477/}
}