Dyfyniad APA

Samuelson Paul & Nordhaus, W. D. (2012). Economics (19th.). Tata McGraw Hill.

Dyfyniad Arddull Chicago

Samuelson Paul and William D. Nordhaus. Economics. 19th. Chennai: Tata McGraw Hill, 2012.

Dyfyniad MLA

Samuelson Paul and William D. Nordhaus. Economics. 19th. Tata McGraw Hill, 2012.

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