The application of virtual reality systems in architectural design processes / Geert T.A. Smeltzer, Jo M.M. Mantelers, Walther A.H. RoelenA proposal for a distributed virtual reality system for architectural simulations / A.H.A. Brouwer, W.A.H. Roelen, J.A.G. JessConjoint analysis and virtual reality : exploring the possibilities / Jan Dijkstra, Harry J.P. Timmermans, Walther A.H. Roelen