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On the geometric structure of hypersurfaces of conullity two in Euclidean space. (English) Zbl 1119.53006
Mladenov, Ivaïlo (ed.) et al., Proceedings of the 8th international conference on geometry, integrability and quantization, Sts. Constantine and Elena, Bulgaria, June 9–14, 2006. Sofia: Bulgarian Academy of Sciences (ISBN 978-954-8495-37-0/pbk). 169-183 (2007).
Summary: We introduce the notion of a semi-developable surface of codimension two as a generalization of the notion of a developable surface of codimension two. We give a characterization of the developable and semi-developable surfaces in terms of their second fundamental forms. We prove that any hypersurface of conullity two in Euclidean space is locally a foliation of developable or semi-developable surfaces of codimension two.
##### MSC:
 53A07 Higher-dimensional and -codimensional surfaces in Euclidean $n$-space
##### Keywords:
semi-developable; second fundamental forms