La courbure totale absolue minimale des surfaces dans
La fonction zeta d'une monodromie.
Legendrian dual surfaces in hyperbolic 3-space
We consider surfaces in hyperbolic 3-space and their duals. We study flat dual surfaces in hyperbolic 3-space by using extended Legendrian dualities between pseudo-hyperspheres in Lorentz-Minkowski 4-space. We define the flatness of a surface in hyperbolic 3-space by the degeneracy of its dual, which is similar to the case of the Gauss map of a surface in Euclidean 3-space. Such surfaces are a kind of ruled surfaces. Moreover, we investigate the singularities of these surfaces and the dualities...
Local Normal Forms of Functions.
Local structure of the zero-sets of differentiable mappings and application to bifurcation theory.
Local Topological Properties of Differentiable Mappings. I.