FAO. (1989). FAO conservation guide N.13.5: Watershed management field manual: Road design and construction in sensitives water-sheds. Rome: FAO.
Dyfyniad Arddull ChicagoFAO. FAO Conservation Guide N.13.5: Watershed Management Field Manual: Road Design and Construction in Sensitives Water-sheds. Rome: FAO, 1989.
Dyfyniad MLAFAO. FAO Conservation Guide N.13.5: Watershed Management Field Manual: Road Design and Construction in Sensitives Water-sheds. Rome: FAO, 1989.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.