An Algebraic Semantics for Object-Oriented Behaviour Modeling. - Jan-Willem G. M. Hubbers; Arthur H. M. ter Hofstede (Australian Software Engineering Conference, 1996)

Formalization of Communication and Behaviour in Object-Oriented Analysis. - Jan-Willem G. M. Hubbers; Arthur H. M. ter Hofstede (Data Knowl. Eng., 1997)