Gaya APA
Hariyanto, S. (2010).
English Business Correspondence : A Practical Guide for Business and Secretarial Student and Professional Secretaries (Cet. 5).
Yogyakarta:
Kanisius.
Gaya MLA
Hariyanto, Sugeng.
"English Business Correspondence : A Practical Guide for Business and Secretarial Student and Professional Secretaries".
Cet. 5
Yogyakarta:
Kanisius,
2010.
Monograf.