Gould, J., Nove, A., & King, M. D. (1968). Penguin Social Sciences Survey. Harmondsworth: Penguin Books.
Dyfyniad Arddull ChicagoGould, Julius, Alec Nove, and Michael D. King. Penguin Social Sciences Survey. Harmondsworth: Penguin Books, 1968.
Dyfyniad MLAGould, Julius, et al. Penguin Social Sciences Survey. Harmondsworth: Penguin Books, 1968.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.