Covey, S. R. (1990). The seven habits of highly effective people: Restoring the character ethic (1st Fireside ed., [repr.].). Fireside.
Cita Chicago Style (17a ed.)Covey, Stephen R. The Seven Habits of Highly Effective People: Restoring the Character Ethic. 1st Fireside ed., [repr.]. New York: Fireside, 1990.
Cita MLA (9a ed.)Covey, Stephen R. The Seven Habits of Highly Effective People: Restoring the Character Ethic. 1st Fireside ed., [repr.]. Fireside, 1990.
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