Dyfyniad APA

Samuelson, P. A., & Nordhaus, W. D. (2010). Economics (19th ed.). McGraw-Hill Irwin.

Dyfyniad Arddull Chicago

Samuelson, Paul A., and William D. Nordhaus. Economics. 19th ed. New Delhi: McGraw-Hill Irwin, 2010.

Dyfyniad MLA

Samuelson, Paul A., and William D. Nordhaus. Economics. 19th ed. McGraw-Hill Irwin, 2010.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.