Covey, S. R. (2004). The 7 habits of highly effective people. Pocket books.
Chicago Style aipamenaCovey, Stephan R. The 7 Habits of Highly Effective People. London: Pocket books, 2004.
MLA aipamenaCovey, Stephan R. The 7 Habits of Highly Effective People. Pocket books, 2004.
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