Dyfyniad APA

Smith, L. C. (2011). The world in 2050: Four forces shaping civilization's northern future. Dutton ; Penguin.

Dyfyniad Arddull Chicago

Smith, Laurence C. The World in 2050: Four Forces Shaping Civilization's Northern Future. New York: Dutton ; Penguin, 2011.

Dyfyniad MLA

Smith, Laurence C. The World in 2050: Four Forces Shaping Civilization's Northern Future. Dutton ; Penguin, 2011.

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