Dyfyniad APA

Gorle, P., & Long, J. (1973). Essentials of product planning. McGraw-Hill.

Dyfyniad Arddull Chicago

Gorle, Peter, and James Long. Essentials of Product Planning. London: McGraw-Hill, 1973.

Dyfyniad MLA

Gorle, Peter, and James Long. Essentials of Product Planning. McGraw-Hill, 1973.

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