Letter to the Editor—Note on the Letter by Morávek and Vlach

Abstract

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Combinatorics and geometry of transportation polytopes: An update

“…As the number of indices grows the possible form and shape of constraints grows. There has been very active work on understanding the corresponding polyhedra (see e.g., [86,87,115,116,129,131,132,133,141]). As we will see here the case of 3-way transportation problems, i.e., three indices, is already so complicated that in a sense contains all polyhedral geometry and combinatorial optimization!…”

On maintenance of the opportunity list for class-teacher timetable problems

“…However, there are two sets of conditions which are of interest because they are natural extensions of the simple conditions and the Gotlieb conditions. THEOREM Moravek and Vlach [9] and restated by Haley [4] for the multi-index problem.…”

A generalized‐indices transportation problem

“…Theorems for the existence of a solution to the three-indices problem have been presented by Haley [6,7,81,by Moravek and Vlach [91, and by Smith [121. Corban 121 has also solved the multi-index transportation problem.…”