@article {aksen2010budget, title = {The budget constrained r-interdiction median problem with capacity expansion}, journal = {Central European Journal of Operations Research}, volume = {18}, number = {3}, year = {2010}, pages = {269{\textendash}291}, publisher = {Springer-Verlag}, author = {Aksen, Deniz and Piyade, Nuray and Necati Aras} }