Dyfyniad APA

Tietze, C., & Lewit, S. (1981). Abortion in the seventies. The Population Council.

Dyfyniad Arddull Chicago

Tietze, Christopher, and Sarah Lewit. Abortion in the Seventies. New York: The Population Council, 1981.

Dyfyniad MLA

Tietze, Christopher, and Sarah Lewit. Abortion in the Seventies. The Population Council, 1981.

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