Dyfyniad APA

Turner, J. S. H., & Helms, D. B. (1987). Lifespan development (3rd.). Holt, Rinehart and Winston.

Dyfyniad Arddull Chicago

Turner, Jeffrey S Helms, and Donald B. Helms. Lifespan Development. 3rd. London: Holt, Rinehart and Winston, 1987.

Dyfyniad MLA

Turner, Jeffrey S Helms, and Donald B. Helms. Lifespan Development. 3rd. Holt, Rinehart and Winston, 1987.

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