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On Shepard's duality theorem
Jacobsen, S. E., (1972)
Convergence results and approximations for optimal (s,S) policies
Hordijk, Arie, (1974)
Minimum concave-cost solution of Leontief substitution models of multi-facility inventory systems
Veinott jr., Arthur F., (1969)
A procedure for computing the K best solutions to discrete optimization problems and its application to the shortest path problem
Lawler, Eugene L., (1972)
The quadratic assignment problem
Lawler, Eugene L., (1963)
The Quadratic Assignment Problem