Dyfyniad APA

Ashenfelter, O., & Rouse, C. (1997). Income, schooling, and ability: Evidence from a new sample of identical twins. National Bureau of Economic Research.

Dyfyniad Arddull Chicago

Ashenfelter, Orley, and Cecilia Rouse. Income, Schooling, and Ability: Evidence from a New Sample of Identical Twins. Cambridge: National Bureau of Economic Research, 1997.

Dyfyniad MLA

Ashenfelter, Orley, and Cecilia Rouse. Income, Schooling, and Ability: Evidence from a New Sample of Identical Twins. National Bureau of Economic Research, 1997.

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