Alexander A. Ageev, Yinyu Ye, Jiawei Zhang. Improved Combinatorial Approximation Algorithms for the k-Level Facility Location Problem. In Jos C. M. Baeten, Jan Karel Lenstra, Joachim Parrow, Gerhard J. Woeginger, editors, Automata, Languages and Programming, 30th International Colloquium, ICALP 2003, Eindhoven, The Netherlands, June 30 - July 4, 2003. Proceedings. Volume 2719 of Lecture Notes in Computer Science, pages 145-156, Springer, 2003. [doi]
Abstract is missing.