1. Archer, A., Rajagopalan, R., Shmoys, D.B.: Lagrangian relaxation for the kmedian problem: new insights and continuity properties. In: Proc. 11th European Symp. on Algorithms (ESA), pp. 31–42 (2003)
2. Arya, V., Garg, N., Khandekar, R., Munagala, K., Pandit, V.: Local search heuristic for k-median and facility location problems. In: Proc. 33rd Symp. Theory of Computing (STOC), pp. 21–29. ACM, New York (2001)
3. Chakrabarti, S., Phillips, C.A., Schulz, A.S., Shmoys, D.B., Stein, C., Wein, J.: Improved scheduling algorithms for minsum criteria. In: Automata, Languages and Programming, pp. 646–657 (1996)
4. Charikar, M., Chekuri, C., Feder, T., Motwani, R.: Incremental clustering and dynamic information retrieval. In: Proc. 29th Symp. Theory of Computing (STOC), pp. 626–635. ACM, New York (1997)
5. Charikar, M., Guha, S.: Improved combinatorial algorithms for the facility location and k-median problems. In: Proc. 40th Symp. Foundations of Computer Science (FOCS), pp. 378–388. IEEE, Los Alamitos (1999)