@article {10438,
	title = {Network hub location problems: The state of the art},
	journal = {European Journal of Operational Research},
	volume = {190},
	year = {2008},
	pages = {1-21},
	url = {https://doi.org/10.1016/j.ejor.2007.06.008},
	author = {Alumur, S. and Kara, B.Y.}
}