Troy Lee Adi Shraibman Disjointness Is Hard in the Multi-party Number-on-the-Forehead Model. 81-91 2008 IEEE Conference on Computational Complexity http://doi.ieeecomputersociety.org/10.1109/CCC.2008.29 conf/coco/2008 db/conf/coco/coco2008.html#LeeS08