J. Arcade, M. Godet, F. Meunier, и F. Roubelat. Futures Research Methodology, American Council for the United Nations University: The Millennium Project, (1999)
V. Augusto, X. Xie, и F. Grimaud. 3rd Annual IEEE International Conference on Automation Science and Engineering, стр. 231--236. Scottsdale, AZ, USA, IEEE, (сентября 2007)