Dyfyniad APA

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

Dyfyniad Arddull Chicago

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

Dyfyniad MLA

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

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.