La structure de certains problèmes d'affectation
Landau's and Rado's theorems and partial tournaments.
Les arrangements d'hyperplans : un chapitre de géométrie combinatoire
Linear independences in bottleneck algebra and their coherences with matroids.
Linear programming duality and morphisms
In this paper we investigate a class of problems permitting a good characterisation from the point of view of morphisms of oriented matroids. We prove several morphism-duality theorems for oriented matroids. These generalize LP-duality (in form of Farkas' Lemma) and Minty's Painting Lemma. Moreover, we characterize all morphism duality theorems, thus proving the essential unicity of Farkas' Lemma. This research helped to isolate perhaps the most natural definition of strong maps for oriented matroids....
Local equivalence of transversals in matroids.