Dyfyniad APA

Advance Directives (2015). National Cancer Institute Member Services.

Dyfyniad Arddull Chicago

Advance Directives (2015). National Cancer Institute Member Services.

Dyfyniad MLA

Advance Directives (2015). National Cancer Institute Member Services.

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