United Nations Industrial Development Organization. (1977). Information sources on the iron and steel industry. United Nations.
Dyfyniad Arddull ChicagoUnited Nations Industrial Development Organization. Information Sources on the Iron and Steel Industry. New York: United Nations, 1977.
Dyfyniad MLAUnited Nations Industrial Development Organization. Information Sources on the Iron and Steel Industry. United Nations, 1977.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.