8Sushil K. Sharma. Webservices architechure for M-Learning. EJEL, 2004, 2 (1): 203--216.
9Plaxton C , Rajaraman R , Richa A . Accessing nearby copies of replicated objects in a distributed environment [C]// Theory of Computing Systems. In Proceedings of the ACM SPAA. Rhode Island: Springer New York,1999: 241-280
10Castro M,Druschel P,Kermarrec A,et al. Splitstream: High-bandwidth content distribution in cooperative environments[C]//Second International Workshop on Peer-to-Peer Systems Ⅱ. In Proceedings of IPTPS03. USA: Lecture Notes in Computer Science, 200:3: 292- 303