Dyfyniad APA

(1999). A twentieth century American reader. Washington, D.C: United States Department of State.

Dyfyniad Arddull Chicago

A Twentieth Century American Reader. Washington, D.C: United States Department of State, 1999.

Dyfyniad MLA

A Twentieth Century American Reader. Washington, D.C: United States Department of State, 1999.

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