Gaya APA
Alexander, L.G.. (1984).
Practice and progress .
Singapore:
Longman Group Ltd.
Gaya Chicago
Alexander, L.G..
Practice and progress.
Singapore:
Longman Group Ltd,
1984.
Text.
Gaya MLA
Alexander, L.G..
Practice and progress.
Singapore:
Longman Group Ltd,
1984.
Text.
Gaya Turabian
Alexander, L.G..
Practice and progress.
Singapore:
Longman Group Ltd,
1984.
Print.