Gaya APA
Essential grammar in use. (1998).
Cambridge:
Cambrigde University Press.
Gaya Chicago
Essential grammar in use.
Ed.2, Cet.7.
Cambridge:
Cambrigde University Press,
1998.
.
Gaya MLA
Essential grammar in use.
Ed.2, Cet.7.
Cambridge:
Cambrigde University Press,
1998.
.
Gaya Turabian
Essential grammar in use.
Cambridge:
Cambrigde University Press,
1998.
.