Gaya APA

Sholikhah, I, M. et al (1985). Letter Perfect: An Abc For Business Writers (Ed. 1). USA : The Bobbs-Merrill Company, Inc.

Gaya MLA

Sholikhah, Ika, Maratus. et al. "Letter Perfect: An Abc For Business Writers". Ed. 1 USA : The Bobbs-Merrill Company, Inc, 1985. Text.