Gaya APA
G, S. et al (2005).
Being competent in english for senior high school students language programme year XII .
Surakarta:
Gramedia widia sarana indonesia.
Gaya MLA
G, Suharto. et al.
"Being competent in english for senior high school students language programme year XII".
Surakarta:
Gramedia widia sarana indonesia,
2005.
Buku Penunjang.