Dyfyniad APA

Lipsey, R. G. (1971). An introduction to positive economics. ELBS.

Dyfyniad Arddull Chicago

Lipsey, Richard G. An Introduction to Positive Economics. London: ELBS, 1971.

Dyfyniad MLA

Lipsey, Richard G. An Introduction to Positive Economics. ELBS, 1971.

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