UML, OCL, MDA, and SBVR

www.uml.org/. The OMG’s Web site on UML.

www-st.inf.tu-dresden.de/ocl/. Portal on the Object Constraint Language.

www.omg.org/mda/. Model Driven Architecture (MDA).

http://omg.org/technology/documents/bms_spec_catalog.htm#SBVR OMG Web site on SBVR.

http://en.wikipedia.org/wiki/Semantics of Business Vocabulary and Rules. Wikipedia article on SBVR.