@article{CMH_1941__14_138786,
     author = {Ch. Blanc},
     title = {Le type d'une surface et sa courbure totale.},
     journal = {Commentarii mathematici Helvetici},
     pages = {230--233},
     publisher = {mathdoc},
     volume = {14},
     year = {1941},
     zbl = {68.0169.01},
     url = {http://geodesic.mathdoc.fr/item/CMH_1941__14_138786/}
}