Gaya APA
Kilbey, Liz. (2007).
Challenges: workbook 1 .
Inggris:
Pearson Education.
Gaya Chicago
Kilbey, Liz.
Challenges: workbook 1.
Inggris:
Pearson Education,
2007.
Text.
Gaya MLA
Kilbey, Liz.
Challenges: workbook 1.
Inggris:
Pearson Education,
2007.
Text.
Gaya Turabian
Kilbey, Liz.
Challenges: workbook 1.
Inggris:
Pearson Education,
2007.
Print.