@article{JMPA_1926_9_5__1_0,
     author = {Cartan, \'Elie},
     title = {Sur les sph\`eres des espaces de {Riemann} \`a trois dimensions},
     journal = {Journal de Math\'ematiques Pures et Appliqu\'ees},
     pages = {1--18},
     publisher = {Gauthier-Villars},
     volume = {9e s{\'e}rie, 5},
     year = {1926},
     language = {fr},
     url = {http://www.numdam.org/item/JMPA_1926_9_5__1_0/}
}