14 James Surowiecki, The Wisdom of Crowds: Why the many are smarter than the few and how collective wisdom  shapes business, economies, societies and nations (Knopf Doubleday, 2004).
15 Elizabeth G. Chambers, Mark Fouldon, Helen Handfield-Jones, Steven M. Hankin, Edward G. Michaels III  1998, The War for Talent, McKinsey Quarterly; Elizabeth L. Axelrod, Helen Handfield-Jones, and Timothy A. Welsh 2001, The War for Talent, Part Two, McKinsey Quarterly .