Gregory, R. L. (1990). Eye and Brain: The Psychology of Seeing (4th ed.). Princeton University Press.
Dyfyniad Arddull ChicagoGregory, Richard L. Eye and Brain: The Psychology of Seeing. 4th ed. New Jersey: Princeton University Press, 1990.
Dyfyniad MLAGregory, Richard L. Eye and Brain: The Psychology of Seeing. 4th ed. Princeton University Press, 1990.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.