Gaya APA
HUTABARAT, R., SALLAMA, N, I, [.
(2010).
Practical bank letter writing :
.
Jakarta:
Erlangga.
Gaya MLA
HUTABARAT, Roselyne., SALLAMA, Novietha, Indra, [ed.].
"Practical bank letter writing :".
Jakarta:
Erlangga,
2010.
Buku.