Dyfyniad APA

National Book Trust. (1972). National catalogue of university level books. National Book Trust.

Dyfyniad Arddull Chicago

National Book Trust. National Catalogue of University Level Books. National Book Trust, 1972.

Dyfyniad MLA

National Book Trust. National Catalogue of University Level Books. National Book Trust, 1972.

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