Wanfeng Dou Ming Zhu Qi Shen Cooperative Multi-Versioning Technique Based on Version Replication. 159-164 2006 conf/cscwd/2006 CSCWD http://dx.doi.org/10.1109/CSCWD.2006.253033 db/conf/cscwd/cscwd2006.html#DouZS06