Gaya APA
King, F.
(1991).
English business letters
(
Cet.4)
.
Logman Singapore:
Logman Group UK Limited.
Gaya MLA
King, F.W..
"English business letters".
Cet.4
Logman Singapore:
Logman Group UK Limited,
1991.
Buku Pend. Bahasa Inggris.