Petko Bakalov Erik G. Hoel Sudhakar Menon Vassilis J. Tsotras Versioning of Network Models in a Multiuser Environment. 6-24 2009 SSTD http://dx.doi.org/10.1007/978-3-642-02982-0_4 conf/ssd/2009 db/conf/ssd/sstd2009.html#BakalovHMT09