Dyfyniad APA

Heyck. Age of System. Johns Hopkins University Press.

Dyfyniad Arddull Chicago

Heyck. Age of System. Johns Hopkins University Press.

Dyfyniad MLA

Heyck. Age of System. Johns Hopkins University Press.

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