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An O[n2] simplex algorithm for a class of linear programs with tree structure
Schreck, H., (1985)
Finding embedded network rows in linear programs : I ; Extraction heuristics
Bixby, Robert E., (1988)
Heterogeneity, control variables, and maximizing behaviour : theory and an application to earnings functions with labor mobility
Hübler, Olaf, (1986)
A network flow procedure for project crashing with penalty nodes
Kanda, Arun, (1984)