Soon-Kyeong Kim David A. Carrington A Formal Object-Oriented Approach to defining Consistency Constraints for UML Models. 87-95 2004 conf/aswec/2004 Australian Software Engineering Conference http://csdl.computer.org/comp/proceedings/aswec/2004/2089/00/20890087abs.htm db/conf/aswec/aswec2004.html#KimC04