World Health Organization. (1997). Determination of airborne fibre number concentrations. World Health Organization.
Dyfyniad Arddull ChicagoWorld Health Organization. Determination of Airborne Fibre Number Concentrations. Geneva: World Health Organization, 1997.
Dyfyniad MLAWorld Health Organization. Determination of Airborne Fibre Number Concentrations. World Health Organization, 1997.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.