Jeroen Hoppenbrouwers Bram van der Vos S. Hoppenbrouwers NL Structures and Conceptual Modelling: Grammalizing for KISS. 79-92 1997 23 Data Knowl. Eng. 1 db/journals/dke/dke23.html#HoppenbrouwersVH97 http://dx.doi.org/10.1016/S0169-023X(97)00011-6