Tieying Zhang Jianming Lv Xueqi Cheng Mediacoop: Hierarchical Lookup for P2P-VoD Services. 486-493 2009 ICPP http://doi.ieeecomputersociety.org/10.1109/ICPP.2009.58 conf/icpp/2009 db/conf/icpp/icpp2009.html#ZhangLC09