Dyfyniad APA

Peterson, W. L. (1986). Principles of ecconomics. Universal Book Stall.

Dyfyniad Arddull Chicago

Peterson, Willis L. Principles of Ecconomics. New Delhi: Universal Book Stall, 1986.

Dyfyniad MLA

Peterson, Willis L. Principles of Ecconomics. Universal Book Stall, 1986.

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