1. Ackoff R.L., 1979, The future of operational research is past, Jnl.Op.Res. Soc., 30:93.
2. Ackoff R.L., 1979, Resurrecting the future of operational research, Jnl.Op. Res.Soc., 30:189.
3. Blackett P.M.S., 1962, “Studies of War”, Oliver and Boyd, Edinburgh.
4. Boothroyd H., 1978, “Articulate Intervention”, Taylor and Francis, London.
5. Checkland P.B., 1981, “Systems Thinking, Systems Practice”, John Wiley, Chichester.