Gaya APA
Renn, Diana. (2003).
Contemporary english workbook 4 (2nd).
Boston:
McGraw Hill Contemporary.
Gaya Chicago
Renn, Diana.
Contemporary english workbook 4.
2nd
Boston:
McGraw Hill Contemporary,
2003.
Text.
Gaya MLA
Renn, Diana.
Contemporary english workbook 4.
2nd
Boston:
McGraw Hill Contemporary,
2003.
Text.
Gaya Turabian
Renn, Diana.
Contemporary english workbook 4.
2nd
Boston:
McGraw Hill Contemporary,
2003.
Print.