Riley, P. (2011). Economics. Viva Books.
Dyfyniad Arddull ChicagoRiley, Pippa. Economics. N.Delhi: Viva Books, 2011.
Dyfyniad MLARiley, Pippa. Economics. Viva Books, 2011.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.
Riley, P. (2011). Economics. Viva Books.
Dyfyniad Arddull ChicagoRiley, Pippa. Economics. N.Delhi: Viva Books, 2011.
Dyfyniad MLARiley, Pippa. Economics. Viva Books, 2011.