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