Gaya APA

R, C, S. (2021). 7 The Habits Of Highly Effective People (Cet 1). Tangeran Selatan: PT Karisma Inti Ilmu.

Gaya MLA

R, Covey, Stephen. "7 The Habits Of Highly Effective People". Cet 1 Tangeran Selatan: PT Karisma Inti Ilmu, 2021. Reference.