Malthus, T., & Pullen, J. (1989). Principles of Political Economy. Cambridge University Press.
Dyfyniad Arddull ChicagoMalthus, T.R, and John Pullen. Principles of Political Economy. Cambridge: Cambridge University Press, 1989.
Dyfyniad MLAMalthus, T.R, and John Pullen. Principles of Political Economy. Cambridge University Press, 1989.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.