Piotr Habela Krzysztof Kaczmarski Krzysztof Stencel Kazimierz Subieta OCL as the Query Language for UML Model Execution. 311-320 2008 ICCS (3) http://dx.doi.org/10.1007/978-3-540-69389-5_36 conf/iccS/2008-3 db/conf/iccS/iccS2008-3.html#HabelaKSS08