摘要
Oriented Matroids arise as a natural combinatorial abstraction of linear algebra and geometry.Some of the topics were foreseen by Rockafellar.Later,oriented matroids were independently discovered by Bland,Dress and Las Vergnas.As with matroids oriented matroids can be developed from many different axiom systems.In this survey we shall concentrate on some of the more important ones and show how one system can be
基金
This project is supported by the German Research Association (Deutsche Forschungsgemeinschaft, SFB303)
