FAO. (1991). World soil resources reports N.66: World soil resources. Rome: FAO.
Chicago Style CitationFAO. World Soil Resources Reports N.66: World Soil Resources. Rome: FAO, 1991.
Cita MLAFAO. World Soil Resources Reports N.66: World Soil Resources. Rome: FAO, 1991.
Atenció: Aquestes cites poden no estar 100% correctes.