Dyfyniad APA

Ministry of Health. (1997). National Immunization day.

Dyfyniad Arddull Chicago

Ministry of Health. National Immunization Day. 1997.

Dyfyniad MLA

Ministry of Health. National Immunization Day. 1997.

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