Gaya APA

Mandino, O., Harfi, A. (2007). The Greatest Salesman (Cet. 1). Yogyakarta: Olongia.

Gaya MLA

Mandino, OG., Harfi, Alfiyan. "The Greatest Salesman". Cet. 1 Yogyakarta: Olongia, 2007. .