Jörg Kalcsics. The multi-facility median problem with Pos/Neg weights on general graphs. Computers & OR, 38(3):674-682, 2011. [doi]
@article{Kalcsics11, title = {The multi-facility median problem with Pos/Neg weights on general graphs}, author = {Jörg Kalcsics}, year = {2011}, doi = {10.1016/j.cor.2010.08.002}, url = {http://dx.doi.org/10.1016/j.cor.2010.08.002}, tags = {graph-rewriting, rewriting}, researchr = {https://researchr.org/publication/Kalcsics11}, cites = {0}, citedby = {0}, journal = {Computers & OR}, volume = {38}, number = {3}, pages = {674-682}, }