@article{10_21136_CMJ_1951_100027,
     author = {Havl{\'\i}\v{c}ek, Karel},
     title = {Surfaces r\'egl\'ees qui sont enveloppes de sph\`eres},
     journal = {Czechoslovak Mathematical Journal},
     pages = {--197},
     publisher = {mathdoc},
     volume = {01},
     number = {3},
     year = {1951},
     doi = {10.21136/CMJ.1951.100027},
     mrnumber = {0050938},
     zbl = {0048.38903},
     language = {fr},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1951.100027/}
}