Mohammad Taghi Hajiaghayi, Robert D. Kleinberg, Frank Thomson Leighton. Improved lower and upper bounds for universal TSP in planar metrics. In Proceedings of the Seventeenth Annual ACM-SIAM Symposium on Discrete Algorithms, SODA 2006, Miami, Florida, USA, January 22-26, 2006. pages 649-658, ACM Press, 2006. [doi]
Abstract is missing.