Gaya APA
Azar, B, S. (1989).
Understanding and using : English grammar (2nd ed).
Englewood Cliffs, NJ:
Prentice Hall.
Gaya MLA
Azar, Betty, Schrampfer.
"Understanding and using : English grammar".
2nd ed
Englewood Cliffs, NJ:
Prentice Hall,
1989.
Text.