Dyfyniad APA

(1999). Environmental risks and hazards. Prentice Hall.

Dyfyniad Arddull Chicago

Environmental Risks and Hazards. New Delhi: Prentice Hall, 1999.

Dyfyniad MLA

Environmental Risks and Hazards. Prentice Hall, 1999.

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