1. 1) BOUCHET A. Delta-matroids, jump systems and bisubmodular polyhedra. SIAM Journal on Discrete Mathematics. (1995) vol.8, p.17-32.
2. 2) CHANDRASEKARAN R. Pseudomatroids. Discrete Mathematics. (1988) vol.71, p.205-217.
3. 3) CUNNINGHAM W. H. b-matching degree-sequence polyhedra. Combinatorica. (1991) vol.11, p.219-230.
4. 4) EDMONDS J. Submodular functions, matroids, and certain polyhedra. Combinatorial Structures and Their Applications. Gordon and Breach. (1970)
5. 5) BOUCHET A. Greedy algorithm and symmetric matroids. Mathematical Programming. (1987) vol.38, p.147-159.