1. Armstrong, J.S. (1978) Long-range Forecasting. Wiley, New York.
2. Brent, R.J. (1990) Project Appraisal for Developing Countries. Harvester Wheatsheaf, London.
3. Brickhoff, K. (1975) The performance of forecasting groups in computer dialogue and face-to-face discussion. In: A. Linstone and M. Turoff (Eds.), The Delphi method, Addisson-Wesley, London.
4. Churchman, C.W. (1971) The Design of Inquiring Systems. Basic Books, New York.
5. Coast, J., Donovan, J. and Frankel, S. (1996) Priority Setting: the Health Debate. Wiley, New York.