Dyfyniad APA

Samuelson, P. A., & Nordhaus, W. D. (2001). Economics (17th ed.). McGraw-Hill.

Dyfyniad Arddull Chicago

Samuelson, Paul Anthony, and William D. Nordhaus. Economics. 17th ed. Boston, Mass.: McGraw-Hill, 2001.

Dyfyniad MLA

Samuelson, Paul Anthony, and William D. Nordhaus. Economics. 17th ed. McGraw-Hill, 2001.

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