Gaya APA
Sudarwati, T, M., Grace, E. (2006).
Look ahead 1 an english course for senior high school students year x .
Jakarta:
Erlangga.
Gaya MLA
Sudarwati, Th., M.., Grace, Eudia.
"Look ahead 1 an english course for senior high school students year x".
Jakarta:
Erlangga,
2006.
Text.