Jochen Könemann Ojas Parekh David Pritchard Max-Weight Integral Multicommodity Flow in Spiders and High-Capacity Trees. 1-14 2008 WAOA http://dx.doi.org/10.1007/978-3-540-93980-1_1 conf/waoa/2008 db/conf/waoa/waoa2008.html#KonemannPP08