Gaya APA
Business English one. (1988).
London:
Linguaphone Institute Limited.
Gaya Chicago
Business English one.
.
London:
Linguaphone Institute Limited,
1988.
Text.
Gaya MLA
Business English one.
.
London:
Linguaphone Institute Limited,
1988.
Text.
Gaya Turabian
Business English one.
London:
Linguaphone Institute Limited,
1988.
Print.