@article{MZ_1996__223_3_174946,
     author = {Wolfgang K\"uhnel and Markus Becker},
     title = {Hypersurfaces with constant inner curvature of the second fundamental form, and the non-rigidity of the sphere.},
     journal = {Mathematische Zeitschrift},
     pages = {693--708},
     publisher = {mathdoc},
     volume = {223},
     number = {3},
     year = {1996},
     zbl = {0869.53003},
     url = {http://geodesic.mathdoc.fr/item/MZ_1996__223_3_174946/}
}