Dyfyniad APA

Samuelson, P. A., & Nordhaus, W. D. (1998). Economics (16th ed.). Irwin/McGraw-Hill.

Dyfyniad Arddull Chicago

Samuelson, Paul A., and William D. Nordhaus. Economics. 16th ed. Boston, Mass: Irwin/McGraw-Hill, 1998.

Dyfyniad MLA

Samuelson, Paul A., and William D. Nordhaus. Economics. 16th ed. Irwin/McGraw-Hill, 1998.

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