1. Alberti, N., La Commare, U. and Noto La Diega, S., ?Cost Efficiency: An Index of Operational Performance of Flexible Automated Production Environments,?Proceedings of the 3nd ORSA/TIMS Conference on Flexible Manufacturing Systems, K. Stecke and R. Suri (eds.), Elsevier Science Publishers D.V., Amsterdam, pp. 67?72 (August 1989).
2. Apple, J.M.,Material Handling System Design, Ronald Press, New York, NY (1972).
3. Ashayeri, J., Gelders, L. and Wassenhove, L.V., ?A Microcomputer-based Optimization Model for the Design of Automated Warehouses,?International Journal of Production Research, Vol. 23, No. 4, pp. 825?839 (July?August 1985).
4. Au, Tung and Au, Thomas P.,Engineering Economics for Capital Investment Analysis, Allyn and Bacon, Boston, MA (1983)
5. Azzone, G. and Bertele, U., ?Measuring the Economic Effectiveness of Flexible Automation: A New Approach,?International Journal of Production Research, Vol. 27, No. 5, pp. 735?746 (May 1989).