Eydi, Alireza; Khaleghi, Amir; Barzegar, Khaled - In: EURO journal on transportation and logistics 11 (2022), pp. 1-23
In this paper, we study the hierarchical hub network design problem with a ring-star-star structure. In this problem, the hubs are located in two layers. In the first layer, central hubs (main hubs) are located in a ring structure, and in the second layer, secondary hubs are located. Each...