Covey, S. R. (1999). Seven habits of highly effective people (1st.). Pocket books.
Chicago Edition CitationCovey, Stephen R. Seven Habits of Highly Effective People. 1st. London: Pocket books, 1999.
ציטוט MLACovey, Stephen R. Seven Habits of Highly Effective People. 1st. Pocket books, 1999.
אזהרה: ציטוטים אלה לעיתים לא מדויקים ב 100%.