Hallam, A. (1983). Great geological controversies. Oxford: Oxford University Press.
Dyfyniad Arddull ChicagoHallam, Anthony. Great Geological Controversies. Oxford: Oxford University Press, 1983.
Dyfyniad MLAHallam, Anthony. Great Geological Controversies. Oxford: Oxford University Press, 1983.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.