Gaya APA
Harvard, J., Rose, F. (1994).
Guide to Professional & Bussiness Correspondence .
Jakarta Pusat:
PT PUSTAKA BINAMAN PRESSINDO.
Gaya MLA
Harvard, Joseph., Rose, Felix.
"Guide to Professional & Bussiness Correspondence".
Jakarta Pusat:
PT PUSTAKA BINAMAN PRESSINDO,
1994.
Text.