Gaya APA
Speaking 4 : student's book. (2005).
Yogyakarta:
Kanisius (anggota IKAPI).
Gaya Chicago
Speaking 4 : student's book.
.
Yogyakarta:
Kanisius (anggota IKAPI),
2005.
Text.
Gaya MLA
Speaking 4 : student's book.
.
Yogyakarta:
Kanisius (anggota IKAPI),
2005.
Text.
Gaya Turabian
Speaking 4 : student's book.
Yogyakarta:
Kanisius (anggota IKAPI),
2005.
Print.