Gaya APA
Day, R, R. et al (2009).
Impact issues 3 – 20 stimulating issuesnfor discussion and debate in English (Ed. 2).
Hongkong:
Pearson Longman Asia ELT.
Gaya MLA
Day, Richard, R.. et al.
"Impact issues 3 – 20 stimulating issuesnfor discussion and debate in English".
Ed. 2
Hongkong:
Pearson Longman Asia ELT,
2009.
Umum.