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2. M. L. Balinski, “On two special classes of itransportation polytopes”, in M. L. Balinski, ed., Pivoting and Extensions (North-Holland, Amsterdam, 1974) pp. 43–58.
3. M. L. Balinski, “Signature methods for the assignment problem”, to appear in Operations Research.
4. M. L. Balinski, “Signatures des points extrêmes du polyèdre dual du problème de transport”, Comptes Rendus de l’Académie des Sciences de Paris 296 (1983), Série I, 457–459.
5. M. L. Balinski, “The Hirsch conjecture for dual transportation polyhedra”, to appear in Mathematics of Operations Research.