APA aipamena

(2004). Two countries re-infected with polio, as Nigerian state resumes vaccinations. World Health Organization.

Chicago Style aipamena

Two Countries Re-infected With Polio, As Nigerian State Resumes Vaccinations. World Health Organization, 2004.

MLA aipamena

Two Countries Re-infected With Polio, As Nigerian State Resumes Vaccinations. World Health Organization, 2004.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.