Cita APA (7th ed.)

GARTSIDE, L. (1989). Model business letters.-- Ed.3. Binarupa Aksara.

Cita Chicago (17th ed.)

GARTSIDE, L. Model Business Letters.-- Ed.3. Jakarta: Binarupa Aksara, 1989.

Cita MLA (9th ed.)

GARTSIDE, L. Model Business Letters.-- Ed.3. Binarupa Aksara, 1989.