1. H. Baligh and L. Richartz, Vertical Market Structures (Boston, Massachusetts: Allyn and Bacon, Inc., 1967).
2. Conrad Berenson, “The Purchasing Executive’s Adaptation to the Product Life Cycle,” Journal of Purchasing, 3 (May, 1967), 62–68.
3. John Chambers, Satinder Mullick, and Donald Smith, An Executive’s Guide to Forecasting (New York: John Wiley & Sons, Inc., 1974).
4. David Farmer, “Corporate Planning and Procurement: A Checklist Guide,” in Corporate Planning and Procurement, eds. David Farmer and Bernard Taylor (London, England: W. Heineman Ltd., 1975).
5. Jay Forrester, Industrial Dynamics (Cambridge, Massachusetts: Massachusetts Institute of Technology Press, 1961).