Gaya APA
Humphreys, Pamela. (2013).
IELTS Express Upper Intermediate Workbook .
London:
Cengage Learning, Inc.
Gaya Chicago
Humphreys, Pamela.
IELTS Express Upper Intermediate Workbook.
London:
Cengage Learning, Inc,
2013.
Teacher Resource.
Gaya MLA
Humphreys, Pamela.
IELTS Express Upper Intermediate Workbook.
London:
Cengage Learning, Inc,
2013.
Teacher Resource.
Gaya Turabian
Humphreys, Pamela.
IELTS Express Upper Intermediate Workbook.
London:
Cengage Learning, Inc,
2013.
Teacher Resource.