1. Orientability of matroids;Bland;J. Combin. Theory Ser. B,1978
2. Matroides orientables;Las Vergnas;C. R. Acad. Sci. Paris,1975
3. Lecture on matroids;Tutte;J. Res. Nat. Bur. Standards B,1965
4. Matroid Theory;Welsh,1976
5. On the abstract properties of linear dependence;Whitney;Amer. J. Math.,1935