Gaya APA

Covey, S, R. (2004). The 7 Habits Of Highly Effective People: Powerful Lessons In Personal Change . London, New York: Simon & Schuster UK Ld.

Gaya MLA

Covey, Stephen, R.. "The 7 Habits Of Highly Effective People: Powerful Lessons In Personal Change". London, New York: Simon & Schuster UK Ld, 2004. Text.