Whitfield, P. (1993). Natural history of evolution. Doubleday.
Dyfyniad Arddull ChicagoWhitfield, Philip. Natural History of Evolution. London: Doubleday, 1993.
Dyfyniad MLAWhitfield, Philip. Natural History of Evolution. Doubleday, 1993.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.