1. Lecture Notes in Computer Science;S Cook,2002
2. Lecture Notes in Business Information Processing;P Johnson,2013
3. OMG: Object constraint language specification (version 1.1). OMG document (1997).
http://www.omg.org/cgi-bin/doc?ad/97-08-08
4. Vallecillo, A., Gogolla, M.: Adding random operations to OCL. In: Posse, E., Ratiu, D., Selim, G., Zalila, F. (eds.) Proceedings of the Workshop on Model Driven Engineering, Verification and Validation (MODEVVA 2017). CEUR Proceedings (2017)