Gaya APA
Azar, B, S. (1989).
UNDERSTANDING AND USING ENGLISH GRAMMAR .
United States of Amerika:
Prentice Hall Regents.
Gaya MLA
Azar, Betty, Schrampfer.
"UNDERSTANDING AND USING ENGLISH GRAMMAR".
United States of Amerika:
Prentice Hall Regents,
1989.
Text.