The Future is tomorrow 17 prospective studies [Texte imprimé] :
- La Haye: M. Nijhoff Publishers, 1972
- 2 vol.
- Plan Europe 2000 (M. Nijhoff Publishers, La Haye) General prospective studies. .
- Plan Europe 2000 (M. Nijhoff Publishers, La Haye) General prospective studies. .