APA استشهاد

Lipsey, R. G. . .., & Chrystal, . A. K. (1999). Principles of economics (9ed.). Oxford University Press.

استشهاد بنمط شيكاغو

Lipsey, Richard G ., و Aloc K. Chrystal. Principles of Economics. 9ed. New Delhi: Oxford University Press, 1999.

MLA استشهاد

Lipsey, Richard G ., و Aloc K. Chrystal. Principles of Economics. 9ed. Oxford University Press, 1999.