Delegate or Suffocate: the Art of Working Through Others
http://www.globalknowledge.com/training/whitepaperdetail.asp?pageid=502&wpid=38&country=United States
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Egan, Brian Denis
Global Knowledge
2006

Abstract:

Management is delegation. Either learn to delegate or you will be buried in work that others could, and should, be doing. The more people that a manager can put to effective use, the greater the success of the manager. The more efficiently a manger can put people to work, the greater the success of the manager. As you learn to delegate effectively, your productivity and value to a corporation rise.