1. Edmonds, J., “Matroid Partition”, in G.B. Dantzig and A.F. Veinott, Jr. (eds.) Mathematics of the Decision Sciences, American Mathematical Society, Providence, Rhode Island, (1968)
2. Edmonds, J., “Matroids and the Greedy Algorithm”, Matkomatical Programming 1 (1971)
3. Frank, H. and I.T. Frisch, “Communication, Transmission and Transportation Networks”, Addison-Wesley (1971)
4. Hansen, K.H. and J. Krarup, “Improvements of the Held-Karp Algorithm for the Symmetric Traveling-Salesman Problem”, Mathematicat Programming 7 (1974)
5. Harary, F., “Graph Theory”, Addison-Wesley (1969)