Recherche des singularités qui ont rapport à une droite multiple d'une surface
Recherches analytiques sur la surface du troisième ordre qui est la réciproque de la surface de Steiner
Recherches sur les normales que l'on peut, d'un point donné mener à une conique
Reciprocal domains and Cohen-Macaulay -complexes in .
Réciproque d'une proposition sur les coniques homothétiques qui ont le même centre
Reconstructing Plane Sets from Projections.
Recursive constructions for skew resolutions in affine geometries.
Reduction Theory for Fuchsian Groups.
Reflection curves -- new computation and rendering techniques.
Reflection loops of spaces with congruence and hyperbolic incidence structure
In an absolute space with congruence there are line reflections and point reflections. With the help of point reflections one can define in a natural way an addition + of points which is only associative if the product of three point reflection is a point reflection again. In general, for example for the case that is a linear space with hyperbolic incidence structure, the addition is not associative. is a K-loop or a Bruck loop.
Reflections on refractions.
Reflections on spheres and cylinders of revolution.
Regular conditional linear spaces with two consecutive line degrees.
Regular hexagons associated to centroid sharing triangles.
Regular hexagons in normed spaces and a theorem of Walter Benz.
Regular hyperbolic fibrations.
Regular linear spaces.
Regular partial conical flocks.
Regular polygons
Regular polyhedra - old and new.