Temporal Issues in Qualitative Reasoning. - Roy Leitch; Mark Eric Wiegand (ÖGAI, 1989)

Coping with Complexity in Physical System Modelling. - Roy Leitch; Mark Eric Wiegand; Hiok Chai Quek (AI Commun., 1990)

Constructive qualitative simulation of continuous dynamic systems. - Mark Eric Wiegand (1991)