1. Ackoff, R.L. and Sasieni, M. W. (1968) Fundamental of Operations Research, New York: Wiley. An update of Churchman et al.; excellent coverage of modelling principles in Chapters 1 to 4.
2. Checkland, P. and Holwell, S., ‘Classic OR and ‘Soft’ OR — An Asymmetric Complementarity’, in Pidd, M. (2009) Tools for Thinking: Modelling in Management Science, 3rd edn, Chichester: Wiley, 45–60.
3. Churchman, C.W., Ackoff, R.L. and Arnoff, E.L. (1957) Introduction to Operations Research, New York: Wiley. The first complete OR text published. In contrast to most US published MS/OR textbooks (Ackoff and Sasieni excepted), it gives full coverage to modelling principles in Chapters 1 to 7. Chapter 2 has a complete case history of an OR project. (Out of print.)
4. Daellenbach, H. (1979) ‘A family of inventory models with demand met either from stock or by special production runs’, Engineering and Process Economics, June 1979: 141–6.
5. Fildes, R. and Ranyard J.C. (1997) ‘The success and survival of or groups: a review’, Journal of the Operational Research Society, 48: 336–60.