APA aipamena

Nunan, D., & David Nunan. (1999). Speak out. Singapore: International Thomson Asia ELT.

Chicago Style aipamena

Nunan, David, và David Nunan. Speak Out. Singapore: International Thomson Asia ELT, 1999.

MLA aipamena

Nunan, David, và David Nunan. Speak Out. Singapore: International Thomson Asia ELT, 1999.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.