Dyfyniad APA

Clark, J., & Veseth, M. (1987). Economics: Cost and choice. Harcourt brace.

Dyfyniad Arddull Chicago

Clark, J.R, and Michael Veseth. Economics: Cost and Choice. San Diego: Harcourt brace, 1987.

Dyfyniad MLA

Clark, J.R, and Michael Veseth. Economics: Cost and Choice. Harcourt brace, 1987.

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