Gaya APA

Covey, S, R. (2013). The 7 Habits Of Highly Effective People : Powerful Lessons In Personal Change . New York: Simon &Schuster.

Gaya MLA

Covey, Sthepen, R.. "The 7 Habits Of Highly Effective People : Powerful Lessons In Personal Change". New York: Simon &Schuster, 2013. Text.