1. Matroids, graphs and 3-connectivity;Bixby,1979
2. A Combinatorial Decomposition Theory;Cunningham,1973
3. The dependence graph for bases in a matroid;Krogdahl;Discrete Math.,1977
4. L. Lovász, The matroid parity problem, to appear.
5. Connectivity in Graphs;Tutte,1966