Dyfyniad APA

Covey, S. R. (1989). The 7 habits of highly effective people: Restoring the character ethic. Pocket books.

Dyfyniad Arddull Chicago

Covey, Stephen R. The 7 Habits of Highly Effective People: Restoring the Character Ethic. London: Pocket books, 1989.

Dyfyniad MLA

Covey, Stephen R. The 7 Habits of Highly Effective People: Restoring the Character Ethic. Pocket books, 1989.

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