Hauptkrümmungskreise in einem elliptischen Flächenpunkt

Principal circles of curvature in an elliptic point of a surface (Englischer Titel)

Cercles de courbure principaux en un point elliptique de la surface (Französischer Titel)

Kurzbeschreibung: The model shows the neighbourhood of an elliptic point P with the normal of the surface and the two corresponding principal circles of curvature (red). The centers of the latter are located on the normal of the surface, with P not lying between them.