Covey, S. R. (2006). The 8th habit personal workbook (1st Free Press trade pbk. ed.). Free Press.
Chicago-viite (17. p.)Covey, Stephen R. The 8th Habit Personal Workbook. 1st Free Press trade pbk. ed. New York: Free Press, 2006.
MLA-viite (8. p.)Covey, Stephen R. The 8th Habit Personal Workbook. 1st Free Press trade pbk. ed. Free Press, 2006.
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