Gaya APA

Hariyanto, S. (2010). English business correspondence : a practical guide for business and secretarial students and professional secretaries (cet ke-5). Yogyakarta: Kanisius.

Gaya MLA

Hariyanto, Sugeng. "English business correspondence : a practical guide for business and secretarial students and professional secretaries". cet ke-5 Yogyakarta: Kanisius, 2010. Text.