1. Set covering by ordinal cuts I/II;Bowman,1973
2. Kombinatorische Optimierung in Halbgruppen;Burkard,1975
3. An algebraic approach to assignment problems;Burkard,1974
4. A greedy algorithm for solving a certain class of linear programmes;Dunstan;Math. Programming,1973
5. Matroids and the greedy algorithm;Edmonds;Math. Programming,1971