1. Futures studies in the 21st Century: a reality based view;Marien;Futures,2002
2. The Year 2000: A Framework for Speculation on the Next Thirty-Three Years;Kahn,1967
3. The futures field: searching for definitions and boundaries;Amara;The Futurist,1981
4. Why Futures Studies?;Masini,1993
5. Scenarios and Structural Uncertainty;Dreborg,2004