1. Porter, Michael E. (1985). Competitive Advantage Creating and Sustaining Superior Performance, The Free Press, p. 37.
2. ‘Value Chain Analysis, Achieving Excellence in the Things that Really Matter’, http://www.mindto ols.com/pages/article/newTMC_10.html http://ols.com/pages/article/newTMC_10.html
3. Dixon R. David, Lean in the Job Shop, http://www.technicalchange.com/Lean-in-the-job-shop-tracks.html
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