Dyfyniad APA

(2006). Countries of the world and their leaders yearbook, 2007. Gale Group.

Dyfyniad Arddull Chicago

Countries of the World and Their Leaders Yearbook, 2007. Farmington Hills, Mich: Gale Group, 2006.

Dyfyniad MLA

Countries of the World and Their Leaders Yearbook, 2007. Gale Group, 2006.

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