1. Go downstream—the new profit imperative in manufacturing;Wise;Harvard Business Review,1999
2. After the sale is over…;Levitt;Harvard Business Review,1983
3. How to make after sale services pay off;Bundschuh;The McKinsey Quarterly,2003
4. The secret life of factory service centers;Alexander;The McKinsey Quarterly,2002
5. Profiting from spare parts;Gallagher;The McKinsey Quarterly.,2005