Dyfyniad APA

Postel, S. (2005). Liquid assets: The critical need to safeguard freshwater ecosystems. Washington, D.C: Worldwatch Institute.

Dyfyniad Arddull Chicago

Postel, Sandra. Liquid Assets: The Critical Need to Safeguard Freshwater Ecosystems. Washington, D.C: Worldwatch Institute, 2005.

Dyfyniad MLA

Postel, Sandra. Liquid Assets: The Critical Need to Safeguard Freshwater Ecosystems. Washington, D.C: Worldwatch Institute, 2005.

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