David Eppstein. Squarepants in a tree: sum of subtree clustering and hyperbolic pants decomposition. In Nikhil Bansal, Kirk Pruhs, Clifford Stein, editors, Proceedings of the Eighteenth Annual ACM-SIAM Symposium on Discrete Algorithms, SODA 2007, New Orleans, Louisiana, USA, January 7-9, 2007. pages 29-38, SIAM, 2007. [doi]
Abstract is missing.