Dyfyniad APA

(2005). Responsible alcohol service. National Restaurant Association Education Foundation.

Dyfyniad Arddull Chicago

Responsible Alcohol Service. National Restaurant Association Education Foundation, 2005.

Dyfyniad MLA

Responsible Alcohol Service. National Restaurant Association Education Foundation, 2005.

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