@article{MAN_1973__205_162484,
     author = {Ernst A. Ruh},
     title = {Kr\"ummung und differenzierbare {Struktur} auf {Sph\"aren,} {II.}},
     journal = {Mathematische Annalen},
     pages = {113--130},
     publisher = {mathdoc},
     volume = {205},
     year = {1973},
     language = {de},
     url = {http://geodesic.mathdoc.fr/item/MAN_1973__205_162484/}
}