Gaya APA
Linguaphone. (1990).
London:
Linguaphone Institute Limited.
Gaya Chicago
Linguaphone.
.
London:
Linguaphone Institute Limited,
1990.
Buku.
Gaya MLA
Linguaphone.
.
London:
Linguaphone Institute Limited,
1990.
Buku.
Gaya Turabian
Linguaphone.
London:
Linguaphone Institute Limited,
1990.
Buku.