@article{10_4064_cm_46_1_41_44,
     author = {Thomas Hasanis},
     title = {Characterizations of the sphere by the curvature of the second fundamental form},
     journal = {Colloquium Mathematicum},
     pages = {41--44},
     publisher = {mathdoc},
     volume = {46},
     number = {1},
     year = {1982},
     doi = {10.4064/cm-46-1-41-44},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/cm-46-1-41-44/}
}