APA Style
Complete Business Letters. (1995).
Indonesia:
Elex Media Komputindo.
Chicago Style
Complete Business Letters.
1st edition.
Indonesia:
Elex Media Komputindo,
1995.
Text.
MLA Style
Complete Business Letters.
1st edition.
Indonesia:
Elex Media Komputindo,
1995.
Text.
Turabian Style
Complete Business Letters.
Indonesia:
Elex Media Komputindo,
1995.
Print.