@article{SHC_1957-1958__10_1_A3_0,
     author = {Cartan, Henri},
     title = {Ouverts fondamentaux pour le groupe modulaire},
     journal = {S\'eminaire Henri Cartan},
     note = {talk:3},
     pages = {1--12},
     publisher = {Secr\'etariat math\'ematique},
     volume = {10},
     number = {1},
     year = {1957-1958},
     language = {fr},
     url = {http://www.numdam.org/item/SHC_1957-1958__10_1_A3_0/}
}