Jürgen Ebert Udo Kelter Tarja Systä Workshop on comparison and versioning of software models (CVSM 2009). 457-458 2009 ICSE Companion http://dx.doi.org/10.1109/ICSE-COMPANION.2009.5071060 conf/icse/2009c db/conf/icse/icse2009c.html#EbertKS09