Gaya APA
English for Spesicific Purposes: Economics. (1991).
Jakarta:
PT Gramedia.
Gaya Chicago
English for Spesicific Purposes: Economics.
Cet.3.
Jakarta:
PT Gramedia,
1991.
.
Gaya MLA
English for Spesicific Purposes: Economics.
Cet.3.
Jakarta:
PT Gramedia,
1991.
.
Gaya Turabian
English for Spesicific Purposes: Economics.
Jakarta:
PT Gramedia,
1991.
.