Gaya APA
Betty, A, S. (1989).
Understanding and Using English Grammar : Second Edition (Edisi II).
United States of America:
Prentice-Hall, Inc..
Gaya MLA
Betty, Azar, Schrampfer.
"Understanding and Using English Grammar : Second Edition".
Edisi II
United States of America:
Prentice-Hall, Inc.,
1989.
Text.