Dyfyniad APA

Samuelson, P. A., & Nordhaus, W. D. (1992). Economics (14th ed.). McGraw-Hill.

Dyfyniad Arddull Chicago

Samuelson, Paul A., and William D. Nordhaus. Economics. 14th ed. New York: McGraw-Hill, 1992.

Dyfyniad MLA

Samuelson, Paul A., and William D. Nordhaus. Economics. 14th ed. McGraw-Hill, 1992.

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