1. Einige Beiträge zur Theorie symmetrischer Immersionen in Räume konstanter Krümmung;Backes;Doctoral Thesis,1982
2. On symmetric submanifolds of spaces of constant curvature;Backes;Math. Ann.,1983
3. Manifolds of negative curvature;Bishop;Trans. Am. Math. Soc.,1969
4. Rotation hypersurfaces in spaces of constant curvature;Do Carmo;Trans. Am. Math. Soc.,1983
5. Semi-parallelity, multi-rotation surfaces and the helix-property;Dillen;J. Reine Angew. Math.,1993