Gaya APA
Grace, E., Sudarwati, . (2006).
Look ahead an english course: for senior high school students year XI(sma & ma) .
Jakarta:
Erlangga.
Gaya MLA
Grace, Eudia., Sudarwati, .
"Look ahead an english course: for senior high school students year XI(sma & ma)".
Jakarta:
Erlangga,
2006.
Text.