@article{MAN_1973__201_162373,
     author = {Katsumi Nomizu},
     title = {A {Characterization} of {n-Spheres} in {Space} {Forms} and {Its} {Complex} {Analogue.}},
     journal = {Mathematische Annalen},
     pages = {75--80},
     publisher = {mathdoc},
     volume = {201},
     year = {1973},
     zbl = {0234.53049},
     url = {http://geodesic.mathdoc.fr/item/MAN_1973__201_162373/}
}