Hongtao Liu Yun Bai Yuhui Qiu An Incentive Mechanism for Peer-to-Peer File Sharing. 442-447 2007 ICFIE http://dx.doi.org/10.1007/978-3-540-71441-5_48 conf/icfie/2007 db/conf/icfie/icfie2007.html#LiuBQ07