1968-1973: Building Company J. Eekhout bv, Kwintsheul, the Netherlands (regularly)
1970: Institute for Lightweight Structures / Prof.dr. Frei Otto, Stuttgart
1970: Studio Prof.dr. Renzo Piano, Genova
1971 – 1973: Student-assistant at the University of Technology, Faculty of Architecture, TH Delft under Prof. Anton van Kranendonk, Prof. Dick Dicke and Prof. Jaap Oosterhoff (organisation of design & prototype build seminars on tensile structures, pneumatic structures, space frames, tensegrity structures)
1971: “Frei Otto and the Munich Olympic Games”, article of 60 pages in the Italian magazine ‘Zodiac’, edited by Olivetti, supervised by Renzo Piano
1971-1973: Free time work as a student-designer: several architectural commissions: houses and company buildings, all realised.