APA aipamena

(2001). Levels and trends of contraceptive use as assessed in 1998. United Nations.

Chicago Style aipamena

Levels and Trends of Contraceptive Use as Assessed in 1998. New York: United Nations, 2001.

MLA aipamena

Levels and Trends of Contraceptive Use as Assessed in 1998. United Nations, 2001.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.